Part I argues that Locke, in his Second Treatise on Government,[1] sets out a constitutional model, in which executive power is always politically accountable to the legislature—even in times of emergency. This reading of Locke therefore rejects alternative interpretations of prerogative power (as noted below), which would not only allow the executive to act against the letter of the law, but outside of the constitution itself. The Lockean constitution, which always constrains the executive, is a structural division of political power between the executive and legislature (and, as explained in Part II, the judiciary), resembling the modern separation of powers doctrine. This constitution of structure, therefore, contrasts with other forms of government that would, for example, rely on substantive restrictions on princely power or lodge sovereignty in a single republican legislature. While this article examines Locke’s constitutional model in detail and expounds upon it, it is first helpful to explain briefly why Locke embraced this structural solution to the problem of executive power. Its origins lie in his theory of the state of nature and natural law.

Locke’s Second Treatise begins with the pre-political state of nature, in which all men enjoy perfect freedom and equality, subject only to natural law.[2] He equates that law with reason, which “teaches all Mankind, who will but consult it; That being all equal and independent, no one ought to harm another in his Life, Health, Liberty, or Possessions.”[3] The law of nature permits such harm only when individuals defend themselves, seek reparations for injuries to person or property, or restrain and punish the transgressions of others.[4] Therefore, natural law gives everyone a right to self-preservation, just as it imposes a duty to respect the rights of others; an individual can neither slavishly submit to another, nor exercise arbitrary or destructive dominion over others.[5] Rather, one person’s “attemp[t] to get an other Man into his Absolute Power” is to enter into a “State of War” with the other.[6] Like Hobbes, Locke acknowledges the great insecurity of this natural state where, in the absence of higher authority, every person has rights to ascertain, judge, and execute natural law. Being inclined to “ill Nature, Passion and Revenge,” as well as self-interest and imperfect reason, individuals will misuse these rights and attempt to impose their wills upon others.[7]

Consequently, entrance into a “Civil Government is the proper Remedy for the Inconveniences of the State of Nature.”[8] This act establishes a supreme, communal authority that will decide controversies and so avoid dangerous states of war between individuals. Political society therefore exists for the purpose of better realizing natural law and protecting natural rights to life, liberty, and property.[9] With this explanation for the origins of civil government, Locke thereby introduces the rights-security contradiction that has long vexed liberalism’s supporters and provoked its critics. This contradiction, however, is central to Locke’s political thought. As will be explained below, his structural constitution is built around and productively channels the tensions between rights and security. A careful constitutional architecture preserves natural rights insofar as they are compatible with mutual security, at the same time as it accommodates strong but limited executive power.

Locke arrives at his structural solution, and so deals with the rights-security contradiction, in two basic steps. First, in a move similar to that of Hobbes, Locke disembodies the individual’s rights to ascertain, judge, and execute natural law by placing them in the hands of government. Man thereby leaves behind his perfect natural liberty for liberty in a society formed with his consent.[10] In making this transition from a state of nature to civil society, Locke also reconceptualizes natural law itself. The individual no longer pursues and defends his natural rights through the short-sightedness of his own self-interest. Instead, government officials must impartially ascertain, judge, and execute natural law for the benefit of the whole. In this civil society, the maxim “Salus Populi Suprema Lex”[11] underlies the exercise of all political power. Such power, as Locke describes it, is

a Right of making Laws withPenalties of death, and consequently all less Penalties, for the Regulatingand Preserving of Property, and of employing the force of the Community, inthe Execution of the such Laws, and in the defence of the Common-wealth fromForeign Injury, and all this only for the Public Good.[12]

All political actions must be reasonably related to achieve these ends.Otherwise, actions that are not directed towards the public good cease to beexercises of political power (properly so called), but are insteaddespotic.[13] However, what does or does notadvance the above goals becomes a complex political calculation, where theseparate interests of the individual and the community (and thus the balancebetween rights and security) are no longer clear. How natural law is to berealized in civil society is therefore a difficult question of what serves thepublic good.

Because the public good is normatively thin as an animating principle of government, Locke only proposes it as an abstracted moral imperative and justificatory basis for political power.[14] It is simply too difficult to say in advance what the public good dictates in different, perhaps unforeseen circumstances.[15] Just as individuals do in the state of nature, officials and political factions might dispute its meaning, necessitating an appeal to the opinions of majorities.[16] Therefore, although he justifies civil government as a cure for the ills of the state of nature, Locke is skeptical about the possibility of preordaining the requirements of the public good. At the same time, he distrusts the abilities and motives of those officials exercising political power. Notwithstanding the basic principle that government should protect life, liberty, and property while ensuring security, natural law is a weak constraining force on government. So long as officials appear to serve these ends, the ambiguity and complexity of the public good means that they will have considerable political discretion and will attract popular deference to their decisions. Consequently, despite the merits of the hypothetical philosopher king, benevolent prince, or assembly of virtuous men, the concentration of political power in any one person, group, or institution runs too great a risk of error, arbitrariness, or abuse in either present or in future, less capable hands.[17] The empowering and limiting aspects of the public good accordingly create a “dialectical problem”, which is “critical to Locke’s enterprise.”[18] Locke must therefore find another, pragmatic solution to the problem of controlling and channelling political power for the public good.

At this point, Locke takes his crucial second step in constructing a constitutional model that can both promote natural rights and provide them with the requisite security. When Locke transfers the individual’s rights to ascertain, judge, and execute natural law to government, he conceptually separates these rational functions from one another. While they are unified in the individual existing in the state of nature, or unified in the person of an absolute ruler, in “well order’d Commonwealths, where the good of the whole is so considered,” they must be divided between different officials or institutions.[19] Where these functions are joined in one prince or assembly, only conscience, virtue, or wisdom can ensure that the ruler obeys the dictates of natural law—an abstract and weak constraining force, as just explained. Moreover, rulers are just as irrational as any other individual and can abuse the political power entrusted to them.[20] As with the man who can judge his own cause in the state of nature, such unity of functions in a fallible ruler ensures neither civil society’s rights nor security in the long-run. In contrast, by properly dividing the functions of ascertaining, judging, and executing natural law between government institutions, officials can oppose and dispute one another in an orderly way. Such political disputation ameliorates passions, prejudices, and errors of judgment. Here, then, is the theoretical foundation for erecting a constitutional structure, through which civil society can argue about and articulate the public good.[21] With this important second step, Locke goes on to lay the groundwork for the modern separation of powers doctrine; he first and foremost seeks to control political power by institutionally dividing it between a legislature and executive.

After conferring political power upon civil government, Locke constructs a tense, yet dynamic, constitution where that power is institutionally divided between a strong executive and a powerful legislature. Each is counterpoised to check and balance the other. Through this constitutional structure, Locke indelibly links political power to the public good in three main ways. First, his constitution prevents a centralization of power (most likely in the executive) that might lead to irrational or arbitrary decision making, and ultimately a descent into tyranny. Second, it further prevents the irrational or arbitrary exercise of power by channelling it through different but coordinate government institutions, each uniquely suited to and responsible for ascertaining, judging, or executing natural law on behalf of the civil society. These natural functions correspond to the legislative, judicial, and executive powers. Third, it results in a dialogical reasoning process between these government institutions. It is through this sometimes cooperative, sometimes confrontational process that civil government determines what, precisely, the public good requires in any particular instance.[22] For Locke, the rational pursuit of the public good—and hence, the legitimate exercise of all political power—cannot be divorced from these constitutional structures and processes. Indeed, the public good and the constitution have such close affinity in Locke’s political universe that it is difficult to tell whether his constitution is merely a means to an end or is partly an end in itself.[23] As pointed out in Part II.B, below, this obfuscation becomes critically important for restraining the executive’s dangerous prerogative claims that he must act outside of the constitution for the greater good.

Just how the Lockean constitution works to control political power (especially executive prerogative), and how it accommodates the courts, is the subject of the remainder of this article. Locke began his examination of government institutions with the legislative power, the representational nature of which built upon his idea that popular consent is the fount of legitimacy for all government authority.[24] However, this article begins with and focuses on executive power for four reasons. First, the danger that arbitrary and abusive executive power might present to the public good highlights the special trust that accompanies all political power, and thus the necessity of structural checks and balances. Second, despite some claims to the contrary, the unitary nature of the executive (even an elected one) deprives it of the same kind of majoritarian justification that might mask or excuse oppressive laws passed by a representative legislature. Third, the executive’s institutional advantages can also be weaknesses. Decisiveness and efficiency can come at the expense of balancing and reconciling various interests of societal factions. Emphasis on group security can also overcome concerns for individual rights. Finally, from a historical perspective, the threat that unrestrained executive power poses to individual rights and the rule of law has long been a preoccupation of Anglo-American constitutional thinking.

The post-9/11 world and the “war on terror” place these concerns in an extraordinary contemporary context and highlight the stresses which crises place on the Lockean constitution. One can only understand the ever-lurking, apparently illiberal contradiction of the prerogative by seeing it within Locke’s structural scheme as a whole. Far from a defect in or exception to Locke’s constitutional order, prerogative is instead a pragmatic, yet intrinsic, component of it. Locke’s executive is indeed formidable, especially where (as explained in the next section) the prerogative allows emergency actions that are, strictly speaking, contra legem. Nevertheless, there is one absolute limitation to its legitimate exercise. Executive attempts to rule against or without an independent legislature, capable of holding him accountable, are not prerogative acts at all, but illegitimate assertions of power. Where such actions seriously undermine the constitution’s structural mechanisms for pursuing the public good, they lead to tyranny and invite resistance.

The necessity of strong, executive emergency power brings with it risks of misuse, a dilemma that has long been a problem for liberal thinkers. However, this article suggests that it is a problem Locke solved with his constitution of structure. Danger to the public good, of course, reaches its height in times of emergency. During such times, public-safety imperatives threaten to trump individual rights, and executive power begins to overshadow the legislature (or, as will be seen, the courts). The moment of prerogative strips bare the rights-security contradiction in Locke’s thought. The executive might act in the absence of or even against established laws, for the greater good of preserving civil society against existential danger. However, this is also where the Lockean constitution operates in its most vital sense. Its structures and processes adapt to prerogative, encourage cautious institutional oversight, and warn of tipping points where the prerogative risks the descent into tyranny. Because Locke strongly links the constitution to the public good, as already noted, the executive cannot easily appeal to the latter as an excuse to violate the former. Rather, the constitution and the public good are so closely entwined that a violation of the constitution is a presumptive violation of the public good. Therefore, despite what some have suggested,[25] the prerogative power cannot be an extraconstitutional one, in the sense that it is completely unaccountable to the legislature (or also, as this article claims, the courts). While the Lockean constitution is flexible enough to tolerate a decisive executive like Lincoln, it will not countenance the pretensions of an absolutist ruler or a sovereign dictator.

The result of such executive hubris is a constitutional crisis. When the executive gathers together the functions of legislating, judging, and executing the law, he exercises arbitrary power over the whole of civil society. Such an attempt threatens a state of war with other government institutions sharing in political power, or with the people themselves. As for executive efforts to subvert the constitution by stealth or corruption, rather than by open declaration or force—that is, when legislative or judicial deference to the executive becomes so extreme, uncritical, and habitual as to be effectively an abdication of their own power and checking functions—Locke leaves it to the people to decide when the constitution has been betrayed by those to whom it had been entrusted. If the constitution’s structures finally fail, then the people have a natural right to revolt and, if necessary, to dissolve and reconstitute civil government altogether.[26] By so prominently advocating a right to revolution, Locke accepts the possibility that his constitution might fail one day, regardless of the quantity and quality of its fail-safes. No liberal constitution can entirely eliminate the possibility that a bold or scheming executive might wield absolute power, or that a politically apathetic people might surrender their liberties to a stern, authoritarian order. However, the failure of the Lockean constitution marks the state of affairs for what it has become: tyranny and slavery.

The section above has given an overview of the theoretical origins and purposes of the Lockean constitution. The remainder of Part II unfolds Locke’s structural design, and examines its institutions and processes more closely. The following sections show in more detail how Locke divides political power between the executive and legislature, and how that legislature checks and balances the former. These sections specifically address the problem of how this constitutional model controls prerogative power in times of emergency. To understand better what prerogative is, however, it is first necessary to see how Locke conceives of other types of executive power, and how they relate to legislative power (discussed separately in the next section).

Locke characterizes executive power, generally speaking, in two ways. The first (and least constitutionally problematic) is the duty to enforce the laws promulgated by the legislature.[27] Because laws “need a perpetual Execution, or an attendance thereunto ... there should be a Power always in being” that is separated from the legislative and lodged in different hands.[28] This power of enforcement—Locke’s “executive power”, used in a narrow sense—fundamentally characterizes the whole executive office, as indicated by the use of the descriptor. In this role, the executive is clearly subordinate to the legislature, although Locke gives him a veto power to check the legislature and protect the independence of his office. The executive is bound to apply the law as it is, and the legislature can seek to alter the authority delegated to him or otherwise hold him accountable for maladministration.[29] As the “Supream Executor” of the law, allegiance to the executive is in fact allegiance to the law itself, rather than to the individual or even the office.[30] Beyond these basic points, Locke spends little more time on executive power, in this narrow sense. The manner in which the executive interprets and executes the standing laws, exercises a veto over their passage, or appoints and directs a myriad of inferior magistrates are all related issues of obvious, day-to-day importance in Locke’s constitution.[31] Nevertheless, this narrow executive power does not really seem to trouble Locke. This article suggests three related reasons for this. First, while there will of course be frequent, quotidian political disputes between the executive and legislature, the exercise of executive power (in this sense) should not usually occasion serious constitutional conflicts between them. Second, whatever statutory discretion the executive enjoys in enforcing the law will itself be narrow, legally circumscribed, and likely subject to close legislative (as well as judicial) oversight. Third, neither aspect of this narrow executive power tends to stress unduly or amplify suddenly the security-rights contradiction within the constitution. Locke’s real worry, revealed in his subsequent discussion on executive power in a much broader sense, is the executive’s non-statutory discretion to deal with the uncertainties of political events and protect civil society in times of unexpected crisis. In addition to executive power narrowly conceived Locke identifies and works to control two other, more constitutionally problematic forms of executive power: the federative and the prerogative.

The executive regularly exercises “Federative Power” over matters such as making war, concluding peace, and conducting foreign affairs.[32] Locke describes it as the power over “War and Peace, Leagues and Alliances, and all the Transactions, with all Persons and Communities without the Commonwealth.”[33] Federative power engages the public as “one Body in the State of Nature.”[34] Thus, it is distinct from the executive power (in Locke’s narrow sense) in terms of its subject matter and personal application, and the allowable degree of discretion.[35] With federative power, the executive tends to exercise political power outwardly from the civil society and to act upon foreign persons. Furthermore, in contrast to the factional debates and institutional dialogue prevalent in domestic politics, the potentially hostile international scene requires that civil society act expeditiously as a unified force. This unity aggregates claims to the public good, intensifies its demands, and faces-up to the dangerous and unpredictable state of nature between nations.[36] Consequently, federative power “is much less capable to be directed by antecedent, standing, positive Laws, than the Executive; and so must necessarily be left to the Prudence and Wisdom of those whose hands it is in, to be managed for the publick good.”[37] In contrast to the slow deliberations of the legislature, the executive possesses institutional virtues of speed, efficiency, and decisiveness that are better suited to deal with rapidly-changing international events. Federative power therefore shifts decision-making initiative to the executive; for Locke, unitary action rather than protracted political deliberation better serves the public good in external affairs of state.

Despite its necessity for security in a dangerous world, federative power presents its own risks to the civil society it preserves. The executive might manipulate foreign affairs, war, or national security concerns in order to increase his prestige, influence, and share of political power. Thus, for instance, “war making is a public good where the optimal assignment of power for the most effective delivery also leads to a great risk that it will be produced for private ends.”[38] Moreover, the executive might redirect the federative power inward to manage affairs within the civil society and act upon its members. Where the boundaries between external and internal security become blurred, there is a greater risk that the executive might abuse federative power; with it, the executive might come to exercise domestic political power without legislative restraint.[39] It is only in spite of such concerns, not because of their absence, that the executive wields federative power in order to safeguard civil society from outside threats and enemies. With federative power, the rights-security contradiction becomes more apparent and constitutional checks and balances become strained.

Executive initiative, however, does mean executive unilateralism. Federative power is therefore not an extraconstitutional power. Rather, the “executive-federative power” together comprises “in truth a single power viewed from different aspects,”[40] legitimized and limited by the executive’s obligation to serve the public good. For this reason, it would also be “impracticable” to place them in different persons.[41] Locke’s distinction between them is not one of kind, but mainly of their direction of exercise and the degrees to which the executive has discretion vis-à-vis legislative deference. That is, there is a distinction in executive “‘umpirage’ between the individuals within the society, and ... the proper organization and direction of the force of the political society with respect to threats which emanate from without.”[42] Thus, just as with the executive’s power to enforce the standing laws, the public good simultaneously justifies and limits federative power. Because of the public good’s close connection to constitutional structure, however, it accommodates federative power only within some sort of institutional checks and balances that bring it under political control. Accordingly, although the legislature’s deliberative processes make it ill-suited for directing the federative power, they do enable cautious oversight of it.

Of course, the nature of international affairs makes it difficult for the legislature either to determine in advance or to judge retrospectively what the public good requires of the executive’s federative power in specific circumstances. Therefore, the same institutional justifications for placing the federative power in executive rather than legislative hands also affect the way that the legislature will conduct its oversight. As explained in the next section, Locke’s legislature remains empowered to pass any law it likes, and so can try to limit or censure the executive in his use of federative power. Notwithstanding this strong formal power, the legislature’s institutional limitations in this field mean that it will likely (and rightly) defer to executive discretion. Furthermore, the effectiveness of any laws it passes will be contingent to some extent on unforeseen future events. The function of laws also shifts from primarily enabling executive authority in domestic affairs to checking it in foreign ones. Legislative deference, a paucity of applicable laws, and the vicissitudes of the international state of nature all give the executive a presumptive freedom in his exercise of the federative power; he may act externally in ways that would be unacceptable in a domestic context. In regard to this power, then, Locke’s legislative check on the executive appears to weaken. Importantly, however, it does not disappear. The legislature will flex its power once again if the executive redirects federative power inward to tamper with domestic affairs. Furthermore, the legislature can still try to constrain the federative power directly, in the unusual event that the risk of executive malfeasance overcomes the legislature’s natural deference.[43] In Locke’s constitutional model, federative power is best understood as not formally delimited, but residing in the executive and resisting—but not foreclosing—legislative interference only due to its particular nature.

It is against Locke’s (narrow) executive and federative powers—as much as against legislative power, as will be seen—that one must conceptualize the prerogative. This power is “nothing, but a Power in the hands of the Prince to provide for the publick good.”[44] This executive discretion is necessary, as

the Law-making Power is not always in being, and is usually toonumerous, and so too slow for the dispatch requisite to Execution: andbecause also it is impossible to foresee, and so by Laws to provide for allAccidents and Necessities that may concern the publick.[45]

The prerogative is therefore defined not only by the substantive requirementthat it serve the public good, but also by the presence of a political exigencywhere the legislature is unable to act in time. As Locke describes it,“Prerogative is nothing but the Power of doingpublick good, without a Rule.”[46]However, he also finds that the prerogative might dictate action “against the direct Letter of the Law” whenthe public good demands.[47] Thus, in extremecases (such as when foreign invasion or attack might be imminent) it might evenbe that the executive must act contralegem to preserve civil society.[48] Locke’s idea of prerogative presents a problem “to understandhow the executive may be constitutionally and legally constrained, and yet alsoretain the latitude to act outside or against the law for the publicgood.”[49]

Some might characterize the prerogative as a unique emergency power, conceptually different from the executive and federative powers. This argument would make the prerogative extraconstitutional and illimitable by the legislature (or the courts).[50] Yet, there are some fundamental similarities between the prerogative and federative powers; both emphasize the uncertainty of events and the need for a swift, energetic response in order to preserve civil society. Indeed, from this perspective, the distinctions between federative and prerogative power also become ones of application and degree, but not of kind. While the federative power externally acts upon subjects outside of the civil society, the prerogative will tend to be inwardly directed; it is in domestic, not foreign, affairs where there is less likely to be a legislative vacuum and more likely to be legal restraints upon executive power.[51] The fact that Locke’s constitutional model already tolerates greater executive discretion in federative matters means that the executive will probably only need to act under prerogative when exceptional domestic circumstances require an unusually swift and unanticipated executive response. Federative power admittedly does not contemplate executive violation of the laws (where they do exist and apply), although a foreign crisis might precipitate recourse to the prerogative at home or abroad. Moreover, one can also conceive of the prerogative contralegem as responding to circumstances so unique that any relevant laws arguably no longer apply, opening up a crack in the legal framework that must be immediately filled by executive action. In either case, under both the federative and prerogative powers, the executive exercises wide discretion to deal with unpredictable security threats that are not amenable to regulation by standing legislation.

Seen in this way, the prerogative, federative, and executive powers are indeed various forms of a unified discretionary power in the executive; prerogative is not on a different conceptual plain. Accordingly, “ordinary” executive discretion under the laws and exceptional discretion under the prerogative stand at different end points on a scale of discretion to be used for the public good. When the whole of Locke’s executive power and the varied circumstances justifying executive discretion are placed on this scale, there is no longer room for extraconstitutional concepts of emergency power or states of emergency. Instead, there are only degrees of executive discretion, legislative deference, and exception from usual legal norms, all of which correspond to the degree of ever-present risks to the security of the civil society.[52] Like any other type of executive discretion, then, the prerogative rests upon a duty to serve the public good, as well as upon institutional advantages for taking quick, decisive action. However, more than any other type of power, the prerogative strips bare the security-rights contradiction and threatens to centralize political power in the executive. Significantly, Locke alludes to this dilemma in his introduction on prerogative, writing that “[w]here the Legislative and Executive Power are in distinct hands,” the public good justifies executive discretion when the legislature is unable to act.[53] The prerogative, just like executive power generally, is limited by the constitution’s structural division of political power (as explained in the first section). Even where executive discretion is at its broadest and most necessary, it comes to an end where the executive attempts to make binding rules, alter or abolish the laws, or does so constructively by dispensing with them and ruling through arbitrary decree. Should the executive attempt any of these actions under a claim of prerogative, the legislature has its own constitutional duty (explained in the next section) to cease its deference to executive discretion and challenge the encroachment upon its own political power. As argued in Part II, similar executive attempts to usurp the judicial power to adjudicate legal rights and obligations would likewise invite resistance.[54]

For these reasons, the prerogative is not an extraconstitutional power in the sense that it is outside of all control by the legislature (or even the courts). This exceptional prerogative power remains subject to constitutional checks and balances for the same reason that it exists—that is, to serve the public good. As explained in the first section, the public good and the constitution are so closely related as to be nearly one and the same. While they together allow broad executive discretion—even so far as to tolerate emergency actions contra legem—they do not countenance institutionally unaccountable executive rule. Prerogative actions that seek to avoid or undermine institutional oversight, then, violate both the public good and the constitution, and so are not, by definition, prerogative ones at all. Rather, such actions are illegitimate and unconstitutional, presenting a new risk of tyranny to the civil society, even as the executive claims to save it from other threats.[55]

At this point, this article argues that there is a further representational aspect to the public good that links it, and consequently the prerogative, to Locke’s constitution of structure. As Locke writes, the prerogative must combine “activism” with discretion and self-restraint;[56] its exercise is subject to a “Fiduciary Trust ... for the safety of the People.”[57] His reference to public safety is best understood broadly against the rights-security contradiction at the centre of his constitutional model. Security is to be ensured against both external threats and tyranny, which results from the concentration of political power in any one person or institution. Indeed, with the line above, Locke specifically refers to the executive’s duty not only to take necessary action when the legislature is not in session or is unable to act, but actually to convene the legislature at regular intervals. He makes clear that “though the Executive Power may have the Prerogative of Convoking and dissolving such Conventionsof the Legislative ... it is not thereby superiour to it.”[58] The executive’s trust is therefore not only to act where the legislature cannot, but also to ensure (and then submit to) a continuous legislative power. In being willingly accountable to that power, the executive also recognizes the legislature’s own claim to represent the people (as will be seen in the next section), who have consensually formed the constitution, chosen the legislature, and entrusted to it an independent share of political power.[59]

Prerogative, as the executive’s share of political power in trust, precludes divine right or any other authoritarian theories of unrestrained executive rule. Rather, “any political society which derives its legitimacy formally from a set of rights of its sovereign which are not derivatives of the wills of his subjects violates the logical preconditions for a legitimate political society.”[60] Thus, the executive shares political power with the legislature not just to prevent the centralization of that power and to promote institutional dialogue conducive to reasonable decision making but also to share power with a representative assembly for the republican purpose of furthering consensual government. The executive has neither a personal right to rule, nor a claim to superior wisdom as to what is or is not in the best interests of the people—even during emergencies. In a civil society arising from popular consent, therefore, the public good (and the constitution) seeks to resolve the security-rights contradiction and give voice to the people whose life, liberty, and property are at stake. The resulting trust creates a representational relationship between the executive and the people (as well as between the legislature and the people), who have consensually delegated political power to, and divided it between, government institutions. For example, the people owe allegiance to the executive only so long as he abides by the law and the constitution, whereas the executive “degrades himself” in their violation.[61] As Locke writes, the executive is only “the Image, Phantom, or Representative of the Commonwealth, acted by the will of the Society, declared in its Laws; and thus he has no Will, no Power, but that of the Law.”[62] Accordingly, although the executive might assert a unitary representational mandate for the whole of the people when exercising the prerogative during an emergency (perhaps even contra legem), his trust nonetheless requires two things: First, he must recognize the representational limits of his own institutional role. Second, he must respect the representational nature of an elected legislature that reconciles competing claims to the public good by rival political factions. The executive’s trust only legitimizes prerogative power, then, while it remains locked within the constitutional framework.[63]

The trust that directs the prerogative is thus different from a contractarian theory of executive authority establishing an agreement between a single ruler and the people. Such agreement might imply not just that the executive possessed certain rights to power, but that he alone was obligated to do what, in his sole judgment, he paternalistically might think best for them.[64] So, while the trust does place a duty on the executive to exercise the prerogative as he judges necessary for the good of the people he represents, it likewise requires that the executive respect and remain accountable to the elected legislature. Locke’s executive, understood in this way, is republican. The trust gives him a representational justification for the prerogative at the same time that it denies the executive the final political judgment as to whether it actually serves the public good. That responsibility, in Locke’s constitutional model, lies with the legislature.

Notwithstanding the importance of, and interpretive controversies over, the nature of executive power, Locke’s constitutional model focuses primarily on the legislative power. Indeed, his conception of executive power is defined against it, because the model hinges on the extent to which the executive has a discretion to act in the absence of (or exceptionally against) standing legislation. Governing through stable rules, reconciling factional interests, and being composed of elected members makes the legislature—not the executive—the central institution of civil government. As Locke writes:

The great end of Mens entering into Society, being the enjoyment oftheir Properties in Peace and Safety, and the great instrument and means ofthat being the Laws establish’d in that Society: The first and fundamental positive Law of allCommonwealths, is the establishing of theLegislative Power; as the firstand fundamental natural Law, which is to govern even theLegislative: It self, is the preservation ofthe Society, and (as far as will consist with the publickgood) of every person in it.[65]

Therefore, “the Legislative mustneeds be the Supream, and all otherPowers in any Members or parts of the Society, derived from and subordinate toit.”[66] Its institutional location willtherefore determine the form of the commonwealth.[67] Influenced by the seventeenth century’s civil wars and thedevelopments leading to the Glorious Revolution, Locke’s emphasis on legislativepower presaged the formal doctrine of parliamentary sovereignty, by whichParliament could check the Crown’s authority, guard against its misconduct, andeven strip it of its ancient prerogatives.[68] Forexample, the legislature would normally have to authorize executiveencroachments upon the liberties of the subject.[69] It might, on the other hand, grant limited rule-makingauthority to the executive, with guidelines as to its allowable exercise.[70] More radically, the legislature could expresslylimit or abolish specific powers historically left solely to executivediscretion, as Parliament did with the 1689 Billof Rights.[71] Legislativelimitations such as these establish boundaries, beyond which the executivecannot act unless he is prepared to do so contralegem under the prerogative.

Legislation, then, prospectively controls executive power (and might seek to correct specific executive abuses), while expressing the legislature’s own assessment of what the public good requires. As previously explained, these legislative checks and balances are Locke’s structural solution to the dialectical problem of simultaneously enabling and restraining executive power. They are at their strongest in domestic matters, which are most amenable to regulation through slow deliberation and standing rules. Furthermore, as already explained, these checks formally apply just as much to control the executive’s slippery federative power in international affairs, as to his exceptional prerogative in times of crisis. However, any legislative response will have less of a proactive, prospective focus and more of a reactive, retrospective one—especially where the legislature must judge whether the executive was justified in acting contra legem. Although normally deferential to executive discretion in federative and prerogative matters, the legislature must nevertheless consider how the executive has used his wide discretion in specific instances, as well as over a protracted period of time. The legislature’s cautious, deferential oversight—combined with its latent, strong power—thus characterizes its checking function over executive power.

Far from being inconsistent with the notion of prerogative, legislative review and approval or disapproval of prerogative decisions is intrinsic to it. Once prerogative is recognized as merely an extreme degree of executive discretion in the absence of applicable law, rather than a conceptually distinct emergency power, there is no basis for theoretically exempting it from legislative control.[72] Instead, there are only circumstantial arguments for more or less legislative deference to the executive, based on their relative abilities and disabilities for taking swift and decisive action. From this perspective, it also becomes conceptually impossible that “the People have incroach’d upon the Prerogative, when they have got any part of it to be defined by positive Laws.”[73] There can be no encroachment, as such, because the executive neither possesses an exclusive, absolute sphere of prerogative authority, nor a freestanding right to govern without or against other institutional oversight.

Despite its great authority, the legislature (like the executive) has no more than a “Fiduciary Power to act for certain ends,” thus holding its political power in trust for the good of the people.[74] The legislature’s trust has a special representational quality, given that Locke provides for its election. Although Locke did not expound upon an electoral system, he nonetheless alluded to public choice in the legislature’s composition:

If the Legislative, or any partof it be [made up] of Representatives, chosen for that time [of assembly] bythe People, which afterwards return into the ordinary state of Subjects, andhave no share in the Legislature but upon a new choice, this power ofchusing must also be exercised by the People, either at certain appointedSeasons, or else when they are summon’d to it.[75]

Being in some way chosen by the people, individual legislators maintainlinks to various societal interests that keep them more directly accountablethan the executive. The electoral process therefore democratically legitimizeslegislative power to check the executive, while that process, in turn, holdsindividual legislators publicly accountable for their failures in office.[76] As an elected assembly, then, the legislature’strust embodies an especially strong representational relationship between it,the people, and the constitution they have consensually formed.

The elected legislature’s fiduciary trust is critical for solving Locke’s problem of controlling prerogative power, especially when the executive claims a mandate to act for the whole of the people; the question is not whether the executive can do wrong, but who will judge his actions and hold him accountable if he does. Some scholars of Locke maintain that only the people themselves, through popular resistance (discussed below), have the right to challenge the executive’s extraconstitutional use of prerogative.[77] This paper argues the contrary. Locke constitutionalizes republican values in an important way: the legislature and the executive share a representational mandate, just as they share political power. When exercising the prerogative, the executive acts on behalf of the people in order to preserve them from danger, but shows restraint to avoid tyranny. When judging that prerogative (with likely deference), the legislature similarly acts for the people in order to guard them from tyranny, while still allowing the executive the discretionary latitude that exigencies demand. Both represent the people from the different perspectives of security and rights, and their mutual trusts mean that one (like security and rights) cannot do without the other.

The legislature—as an elected assembly representing a multitude of political interests—consequently works as an institutional intermediary between the executive and the people. This representational role becomes more pronounced when judging uses of the prerogative in times of emergency. The legislature does this, when in session, by implicitly or expressly acquiescing (or not) to the executive’s decision of the moment. If not in session, it must later consider an act of indemnity for those executive actions against the letter of the law. In turn, the executive (subject to his own trust) is bound to submit to legislative limitations or censure. Executive attempts to thwart the elected legislature through corruption, or outright defiance, show disdain for the legislature’s role as the people’s intermediary, violate the public good, and threaten the constitution. Locke emphasized this point by condemning executive interference with the election of legislators, which might lead to the dissolution of the civil government.[78] The executive also cannot directly and demagogically appeal to the people, in order to get past its elected assembly. Executive subversion of the elected assembly, however attempted or achieved, risks a state of war between the executive and the people.[79] Should that happen, only the people’s right to resist (see below) can save them. It is to prevent such a state that the legislature has its intermediary role. Locke’s constitutional model thus permits “sophisticated institutional representation of the will of the people,” which not only diffuses government power generally, but also channels public resistance against the executive.[80] Consequently, “Legal avenues for redress against tyrannical abuses give effect to the right of resistance without destabilizing the government.”[81] Through this institutional and representational pas de deux or tug-of-war over what the public good requires—and with little normative precommitment—the constitution flexibly controls the prerogative.[82]

Thus, it is only where the legislature is no longer capable of resisting executive abuses—and thus fulfilling its role as intermediary—that the people’s right of resistance actually ripens (although, as Part II argues, the courts now also stand in such an intermediary position that forestalls popular revolution). As already pointed out, the legislature may rightly defer to executive discretion and even indemnify actions that are contra legem. However, it cannot uncritically and habitually surrender its judgment to the executive, so that it abdicates for all practical purposes legislative power and its checking function. It must

govern by promulgated establish’dLaws ... designed for no other end ultimately but the good of the People ... [and] neithermust nor can transfer the Power of makingLaws to any Body else, or place it any where but where thePeople have.[83]

The legislature cannot exercise its popularly entrusted power arbitrarily,abdicate it by complacency, or delegate it away wholesale to the executive. Thepeople then have a right of resistance not only against executive tyranny, butalso against the corrupted legislature that has betrayed its trust.[84] Nevertheless, Locke’s suggestion of periodicelections engages yet another structural backup within his constitutional model,so that the people may correct a legislature that decides poorly or does notadequately check growing or abusive executive power. That is, through elections,the people can oust those legislators failing in their fiduciary obligation, asjudged by the electorate. Elections allow the public to “turn the rascals out”,and replace them with legislators more closely attuned to public sentiment. Onlywhere a sitting legislature has become persistently corrupt, or the electoralsystem is inadequate for correction of the problem, do institutionalized meansfor resistance (that is, the legislature as intermediary) give way to a popularright of revolution. The people, who initially consented to form a politicalsociety and establish a civil government to act on their behalf, then stand onceagain in a state of nature, face to face with the tyrant (whether executive orlegislative).[85] The public has an appeal toHeaven, which is essentially a call to trial by battle, and so possesses moraljustification in rebelling.[86]

The legislature, operating properly as a constitutional intermediary for the people, stabilizes both the constitution and civil society against emergencies and the prerogative. First recourse to the legislature as a check on the executive (rather than to the people’s right to resist) enables the constitution to work flexibly and fluidly (if sometimes under strain), without constant, dangerous social upheavals. Locke’s constitutional model is accordingly self-correcting, preventing frequent descents into tumult by institutionally counterbalancing a strong executive with a powerful legislature.[87] Locke’s famous call for revolution is only an extreme and last recourse against persistent and severe executive abuses, when the legislature is unable or unwilling to intercede on the people’s behalf. Such resistance comes with the dissolution of a civil government and a constitution no longer able to correct abuses. Because the legislature has a special representative mandate for the people and functions as its intermediary, the executive cannot not subvert or bypass it by direct appeals to the people—even pursuant to his own claims to a popular mandate. Should he stubbornly arrogate himself over the legislature, then war might indeed follow between him and the people’s representatives—an institutional struggle for political power like England’s civil wars and the Glorious Revolution, the end of which Locke witnessed. There is, however, one last possible institutional check on the executive (as well as the legislature), which Locke did not describe. This check requires a new institutional addition to his constitutional architecture, but one that still fits with its overall aesthetic of substance and form. That addition is the judiciary, counterpoised against both the executive and legislative branches, and under its own unique fiduciary trust to uphold the rule of law.

Locke’s constitutional model, a forerunner to modern separation of powers theory, rests on a dualistic structure. He divides political power between the executive and legislature, who check and balance one another to prevent the centralization of authority and facilitate dialogical decision making between them. Each of these has its own trust to act for the people, introducing a republican element to his constitution. To the contemporary observer, whether accustomed to the more pronounced American system of separation of powers or the more blurred Westminster variants, an independent judiciary of some sort is notably absent from Locke’s scheme.[88] However, while he gives no specific attention to the role of courts, his constitutional model fundamentally rests on natural rights and the need for a civil government that reasonably judges disputes over them. Adjudication is the essence of politics: “Those who are united into one Body, and have a common establish’d Law and Judicature to appeal to, with Authority to decide Controversies between them, and punish Offenders, are in Civil Society one with another.”[89] Locke asserts the need for appeals against wrongs and judges to settle conflicts, so as to end the destructive state of war between individuals.[90] As suggested in the first section, the surrender of individual rights to ascertain, execute, as well as judge natural law roughly corresponds to his institutional division of legislative and executive powers. Thus, while Locke does not establish an independent judiciary to go along with these, he nonetheless infuses his entire constitution with a judicial power. He considers “the main function of the State as essentially judicial,”[91] even though he appears to combine judicial and legislative power in a way that is not entirely clear in meaning. In a commonwealth, the “Judge is the Legislative, or Magistrates appointed by it.”[92] Such a power, it seems, can be either the legislature in its general capacity to govern society through standing laws, or some lesser officials charged with the administration of justice in specific cases.[93] So while Locke does not institutionalize judicial power separate from and alongside the executive and legislature, his constitutional model leaves ample room for its further development.[94]

Accordingly, one can “read-in” an institutional role for courts to administer justice in specific cases, as well as to temper the exercise of political power generally. Locke states quite clearly that the legislature, though supreme, nevertheless, must govern through “indifferent and upright Judges, who are to decide Controversies by those Laws.”[95] Limited by its trust, the legislature must not only “decide the Rights of the Subject by promulgated standing Laws,” but also by “known Authoris’d Judges.”[96] The legislature can only pass laws that are to be uniformly and equally applied for the public good, can only take property by popular consent, and cannot delegate away its legislative power.[97] From these prohibitions, it is only a short jump to say that courts should fairly administer those laws, treat like cases alike, and ensure that government officials only infringe personal liberties pursuant to lawful authority—all hallmarks of adjudication upon which A.V. Dicey later defined the rule of law.[98] Rejecting arbitrary legislation in this way (as well as, by implication, arbitrary executive enforcement of it), Locke lays the groundwork for the institutionally separate administration of justice, based upon natural law principles. Indeed, Locke’s premise can be related to a modern natural law theory like that of Lon Fuller.[99] A full examination of any connections between the two is not attempted here, but a basic comparison is straightforward enough. Expounding on natural justice, Fuller identifies eight desiderata necessary to a true legal system, and which comprise the “internal morality” of the law.[100] If these requirements are substantially lacking, then the political system is not one based upon law, properly so-called. In that case, what passes as “law” is no longer a purposeful, rational enterprise, but is instead only a tool for the imposition of the ruler’s arbitrary will. Fuller’s purpose for the law is admittedly rather modest, being that of “subjecting human conduct to the guidance and control of general rules.”[101] As such, his conception of natural justice lacks Locke’s normative imperative that government only act for the public good (even though that good is contestable), in order to protect natural rights to life, liberty, and property. Nevertheless, Fuller’s argument is consistent with Locke’s assertion that the legislature’s trust requires that it govern through impartial, predictable, and reasonable laws.[102] Of course, in the Second Treatise, Locke does not discuss anywhere a judicial power like this. Still, his political theory lays the theoretical justifications for articulating such a power, just as his constitutional model of checks and balances can accommodate a sophisticated court system.

Even if one accepts this paper’s interpretation of Locke’s constitutional model, there remain two main objections to including an independent judiciary within it. The first is that Locke himself did not do so; the inclusion would therefore contradict and undermine his legislative-executive dualism, which relies on political instead of legal checks on executive power. That argument is overly rigid, however, and overlooks the fact that Locke’s model is general, flexible in light of local circumstances and historical developments. It also ignores the widespread acceptance of the modern separation of powers theory, whereby the judiciary has assumed a constitutional role equal in station to the legislature and executive. On the other hand, once Locke’s model is modified to include the courts, it then requires some form of judicial controls even on prerogative power and the elected legislature. The second objection, addressed in the next section, is that unelected judges lack the democratic legitimacy to challenge executive emergency actions intended to preserve the public from harm, let alone somehow limit or control acts of the legislature. Accordingly, control of the prerogative is again a political matter, left to the elected legislature. That position is shortsighted, confusing the judiciary’s lack of direct electoral accountability for the absence of a republican trust. Independent and impartial courts exercise their judicial power for the people, so that they have their own representational mandate to preserve the rule of law against executive abuses of power.

The first objection above downplays the fact that Locke’s constitution was both prescriptive of an idealized form of government and descriptive of the constitutional changes he witnessed in the turbulent England of the seventeenth century. From its inception, then, Locke’s model was attuned to political conditions and historical trends, as much as it had emanated from rational theorizing. Locke imagined a constitution that “is not an abstract doctrine,” but that historically “embraces English constitutional practice.”[103] His model is adaptable by nature, and “is designed to be applied beyond the circumstances of its conception, if not everywhere.”[104] As a practicable model, Locke’s constitution invites reinterpretation and application in light of historical experiences and political developments. The same constitutional instability in England that influenced Locke might also have warned him that even his constitutional model might evolve over time, either slowly or through more sudden, momentous changes.[105] Furthermore, his own notion of popular consent as the basis of political society necessarily offered a possibility of change, so long as the basic substantive and structural principles of his constitutional model remained. For example, not long after publication of the Second Treatise, Parliament passed the Act of Settlement of 1701, guaranteeing life tenure for judges, and thereby taking an important step in establishing the independence of the judiciary. Later, the United States Constitution of 1787—emerging from revolution and representing a Lockean moment of the consensual formation of a new political society—clearly elevated the judiciary to its full place within modern separation of powers theory. This development was the culmination of several intellectual influences, but Montesquieu’s thinking, common law ideas, and the articulation of popular sovereignty especially guided judicial power to a Lockean end. As a result of these developments with the modern separation of powers doctrine, the judiciary has attained a crucial constitutional role in preserving the rule of law.[106] It holds its own power in trust for the people and sits comfortably within a new, tripartite constitutional structure. In this modified version of Locke’s model, the executive is no longer just politically accountable to the legislature for its use of the prerogative, but is legally accountable to the courts as well.

Accordingly, a brief look at the American revolutionary era (broadly ranging from the late colonial period to the adoption of the Constitution in 1787) illustrates the historical contingency of Locke’s constitutional model. That is, over time, these events combined with Locke’s ideas in a way that would, over a long period of time, influence and enhance the judiciary’s constitutional prestige throughout the common law countries. Of course, the court systems in these countries have developed in different ways, as have their precise constitutional roles. Nevertheless, the American example surveyed here is particularly significant because Locke was arguably the pre-eminent theoretical influence on American political thinkers and the US Constitution’s innovative system for the separation of powers.[107] His theories of natural rights, the social contract, and constitutional checks and balances potently combined with radical Whig polemics to fortify the revolutionary rhetoric about fundamental liberties and the threat of tyranny.[108] Accordingly, many American thinkers during the period invoked Locke to justify independence, challenge government power, and frame new constitutions at both the state and federal levels.[109] Although polemicists and statesmen took inspiration from many intellectual sources, Locke, Montesquieu, and the English common law remained among the most influential.[110] However, neither the colonial grievances provoking the American Revolution nor the early national troubles leading to the Constitution of 1787 need any explanation here.[111] It is enough to say that the imperial crises arising in the 1760s began a nation-building process leading to the Constitution of 1787, which established a federal government of limited powers delegated by the people. What is important for this article is that American constitutional thinking embodied an idealized Whig vision of government, formalizing the institutional division between executive, legislative, and judicial power along Lockean lines. Thus, American political theory elevated the judiciary to an independent third branch, capable of, and democratically legitimized in, controlling the other two.

After Locke, Montesquieu was among the greatest intellectual influences on the American development of judicial power; he “made Locke’s separation of powers the keystone of his own more splendid arch.”[112] As Montesquieu wrote:

[T]here is no liberty, if the power of judging be not separated from thelegislative and executive powers. Were it joined with the legislative, thelife and liberty of the subject would be exposed to arbitrary control; forthe judge would be then the legislator. Were it joined to the executivepower, the judge might behave with all the violence of an oppressor.[113]

Montesquieu’s constitutional division of power was Lockean, in that itdiffused authority to prevent the accumulation and arbitrary exercise of powerby any one institution. His theory went a step further, however, byinstitutionally separating the judicial function from both the legislative andexecutive powers. Montesquieu’s idea of separation was also flexible, so thatall three powers checked and balanced one another. Each of the three branches,in different ways, could therefore hold the others to their fiduciary trusts (asexplained further below).[114]

Just as Locke’s model reflected the 1689 constitutional settlement, Montesquieu’s inspiration was the early eighteenth-century British constitution. Although that constitution resembled Locke’s legislative-executive dualism (i.e., counterbalancing Parliament and the Crown), Montesquieu took notice of the significant institutional role that the royal courts had assumed in practice. He probably did not imagine judicial power to encompass the nullification of laws, so the judiciary’s power would likely be found only in its impartial adjudication of legal rights and obligations, free from legislative or executive interference.[115] Still, he would have noticed the independence of English judges since the Act of Settlement, the courts’ role in developing the common law, and courts’ use of statutory interpretation to temper legislative power and protect individual liberties. The actual constitutional role of English courts only underscored that Montesquieu’s own classification of government power into three branches was neither a rigidly formalistic one, nor based on a mixed government between Crown, Lords, and Commons—as Blackstone, discussed below, would describe it. Instead, Montesquieu imagined a constitution where Parliament, Crown, and courts checked and balanced one another through their respective legislative, executive, and adjudicatory functions.[116] Montesquieu’s theory thus institutionalized a distinct judicial power by building upon Locke’s originally dualistic structure and furthering its purpose of controlling political power generally.

Along with Locke and Montesquieu, the common law also buttressed revolutionary arguments for an independent judicial power. One can argue that the common law itself had earlier influenced Locke, whose own ideas about natural rights and limited government, in turn, became embedded within it. Apparent links between Lockean thought and the common law resurfaced in Blackstone’s Commentaries—highly influential throughout Britain and its colonies. Blackstone echoed Locke in his discussions on balanced government, natural law, and the consensual basis for political society.[117] He likewise struggled with a similar dialectical problem to Locke; that is, how to justify and limit a sovereign Parliament. To resolve this tension, he elided distinctions between positive and fundamental law: statutes reflected the latter, just as judges “discovered” the common law. This confusion reflected a juristic transition between natural law theories and emerging positivism in English legal thought.[118]

With that confusion, Blackstone inadvertently undermined other constitutional ideas that he was defending. He presented a rationalized, positivistic approach to legal thinking that still maintained strong links with the common law tradition, based upon custom and first principles.[119] Accordingly, Blackstone described a “balanced constitution” that fit quite well with Locke’s constitutional model; both used constitutional structure to realize natural law and address the rights-security contradiction presented by strong civil government. In Blackstone’s constitution, the institutional division of social estates limited government power, just as natural law guided its exercise. Crown, Lords, and Commons combined and balanced each other in the King-in-Parliament. However, by Blackstone’s day, this understanding of the British constitution was already weakening. Many Whigs at home and abroad saw the growth of responsible government, the party system, and political patronage as undermining an idealized, balanced constitution. According to some accounts, this balance of social forces, as well as the institutional separation of legislative and executive power, would be mostly fiction by the early nineteenth century.[120] In any case, Blackstone’s dated view of a class-bound, balanced constitution was not as important as two other undercurrents in his work. First, he had not found a satisfactory resolution between the limits of natural law and legislative power, thereby inviting a constitutional response of some kind. Second, his constitution hinged on the functional division of political power between legislative, executive, and judicial institutions just as much as it did on the institutional balance between old feudal estates. Thus, both Montesquieu and Locke lurked beneath Blackstone’s orthodox description of the British constitution. Parliament passed statutes, judges “found” the common law, and the Crown—possessing its ancient prerogative powers—enforced the law and provided for security. All three institutions worked together to realize natural law in the most practicable way, serve the public good, and check and balance each other.

Blackstone was highly influential in the American colonies, where he was widely read by generations of lawyers, judges, and statesmen. His dated constitutional account even contributed to revolutionary indignation among his Whiggish readers, as it only highlighted the contemporary “corruption” of the ancient constitution. To colonists in opposition, Crown ministers appeared to undermine legislative independence while Parliament seemed increasingly to abuse its power over unrepresented and largely self-governing colonies. In the second half of the eighteenth century, then, this discrepancy between Blackstone’s constitution as practiced and as Whiggishly idealized contributed to the ideological conflicts leading to war and American independence. Blackstone’s role in these developments was ironic, given that he favoured Parliament’s supremacy over the colonies, despite American appeals to natural law. However, some of his language in the Commentaries recalled Chief Justice Coke’s opinion in Dr. Bonham’s Case, suggesting that “when an Act of Parliament is against common right and reason, or repugnant, or impossible to be performed, the common law will controul it, and adjudge such Act to be void.”[121] Accordingly, Blackstone’s discussions on natural law, the power of the courts, and a balanced constitution imparted special, unintended meanings to those Americans concerned that Parliament had unjustly infringed their liberties (or, later, that even state assemblies had legislated with intemperate revolutionary zeal and without other adequate institutional checks). Blackstone thus became the common law bridge over which American constitutional thinking could cross from the balanced constitution of social estates and parliamentary sovereignty to a government of a functional separation of powers, limited by first principles. Inspired by the Commentaries (or, rather, a certain reading of it):

[P]rotesting colonials fused the constitutional rights of Englishmenwith the natural rights of man, thereby merging the views of such legalluminaries and former chief justices of England as Coke, Hobart, and Holt,and the natural law views of Pufendorf, Burlamaqui, and Locke.[122]

The fusion of natural law and common law with a Lockean perspective onconstitutional structures was another critical step in lifting judicial power toan equal place alongside that of the legislature and executive.

Despite Montesquieu’s own admission that judicial power was weaker than the legislative and executive powers, the above influences would combine to inspire the Constitution of 1787, clearly establishing all three as coordinate branches of government.[123] Article III established “The Judicial Power of the United States,” although it did not explicitly set out how the courts would, in practice, check and balance the Congress and the President. Nevertheless, Locke, Montesquieu, the common law, and popular sovereignty (discussed in the next section) laid foundations for the Supreme Court’s eventual assertion of a power to invalidate unconstitutional acts of Congress.[124] To be clear, the purpose of these American examples has not been to argue for a written constitution, insist on the judicial nullification of laws, or disregard historical developments in other countries. Rather, the examples here only illustrate an especially important historical process by which Locke’s executive-legislative dualism evolved into the modern concept of the separation of powers. Under this general doctrine, an independent judicial branch must check and balance the other two powers, but in an effective way, adapted to local political circumstances. The Lockean constitution, so modified and locally applied, still preserves the political dynamic between the executive and the legislative branches. However, it also legalizes their fiduciary trusts in one manner or another. Moreover, in controlling the other branches, the judiciary upholds its own trust to preserve the rule of law. This trust gives the judiciary a representational mandate all of its own. However, one last American example from the revolutionary era—the articulation of popular sovereignty—gives the final, republican justification for judicial control of even prerogative power.

Due to historical developments like those just described, the modern separation of powers doctrine gives the judiciary a constitutional role equal in importance to the legislature and the executive. As such, it is ensconced within a Lockean constitution of checks and balances. Like the other two branches, the judiciary exercises its power in trust on behalf of the people who have consensually delegated that power to it. Even if judges are not electorally accountable (indeed, perhaps just because they usually are not), the judiciary’s trust carries a special, indirect representational mandate to hold impartially both the legislature and the executive to their prescribed powers and to the rule of law. This trust, emanating from the people, therefore has a republican quality. It gives the judiciary an intermediary role between the people and the other two branches, much like the role described earlier for the legislature.[125] Turning once more to the American revolutionary experience for illustration, the doctrine of popular sovereignty shows particularly why judicial power and review of the prerogative is democratically legitimate. Although elsewhere this doctrine developed differently, perhaps less dramatically, and with distinct legal implications, it also came to underpin constitutional government in other common law countries, such as Canada and the United Kingdom itself.[126]

Rebellious American colonists reacted not only against the King, but also against a Parliament that claimed illimitable, sovereign authority to legislate for the unrepresented colonies in their internal matters. To revolutionaries, absolute parliamentary power could be just as arbitrary and tyrannical as unrestrained royal power, a danger many saw in imperial laws like the so-called “Intolerable Acts” of 1774, which (among other things) closed the port of Boston, altered the Massachusetts government, and allowed trials for local crimes in English rather than colonial courts. Such unpopular legislation only proved to many colonists the importance of first principles as restraints upon government power. In much Whiggish American thinking, the rule of law—with some kind of judicial checks on legislative and executive authority—became closely bound up with a constitution and the public good.[127] After achieving independence, however, the Americans still had to struggle with how to control the powers of elected government officials who could claim a representational mandate to do the will of the people, as they perceived it. Republican government, and the new relationship between governors and governed, brought its own dialectal problem about how to empower and control civil government, both at the state and national levels.

In America, where older social distinctions based upon class were weak and political participation was for the time relatively open, Whiggish ideas had long emphasized the power of elected colonial assemblies responsible to local constituencies. Many Americans kept faith after the Revolution that the establishment of popular legislatures, animated by republican virtue and paired with weak governors, would avoid the heavy-handed manner of government that they had attributed to both Parliament and the Crown. Early constitutional experimentation with state governments, however, unfortunately demonstrated that a majority in a republican legislature, without adequate executive or judicial counterweights, could act just as arbitrarily and unwisely as Parliament or the Crown supposedly had.[128] Thus, by 1787, many Americans increasingly understood that no one branch of government (including an elected legislature) could be endowed with unlimited authority.[129] Post-independence experiences with democracy, as reflected in James Madison’s essays numbers 10 and 51 in The Federalist quickly turned into political rough-and-tumbles between rival political factions and sometimes less than virtuous public officials.

Republican government, then, could not be securely entrusted to imperfect legislatures tempted to claim democratic infallibility—a notion that smacked far too much of parliamentary supremacy. Instead, there was a need to emphasize the ultimate sovereignty of the people, who had delegated only limited power to their government institutions and officials, none of which could ever entirely be trusted.[130] Popular sovereignty, therefore, not only propped up and explained Locke’s notion of the public good in clear republican terms, but it also transformed Locke’s checks and balances into a distinctly modern separation of powers theory. As Gordon Wood explains:

The assumption behind this remarkable elaboration and diffusion of theidea of separation of powers was that all governmental power, whether in thehands of governors, judges, senators, or representatives, was essentiallyindistinguishable; ... Only the great changes taking place in these years inthe Americans’ understanding of representation and the people’s relationshipto the government—all culminations of a century and a half of experience inthe New World brought to a head by the anomalies inherent in theconstitution-making experiments and summed up in the new meaning given tothe idea of the sovereignty of the people—made this assumptionpossible.[131]

By the time of the constitutional convention in 1787, most or all of theframers would have already conceived of the sovereignty of the people, whichboth legitimized and limited all forms of government power. This idea clearlybuilt upon Locke’s arguments for the consensual nature of political society andfor the importance of an elected assembly. It also founded the emergingseparation of powers doctrine not upon the institutionalization of a feudalclass system, paternalistic notions of government, or classical ideas ofrepublican virtue, but on democratic representation, rational governingprocesses, and a cautious mistrust of human frailties. As a result, all threebranches came to represent the popular sovereign equally, with eachindependently exercising its limited power on the people’s behalf and with aneye on the actions of the other two. Popular sovereignty thus simultaneouslyempowered and limited government by imbuing three separate branches with theirown competing republican trusts. As such, it resonated with Anglo-American Whigpolemics, which advocated democratic institutions, while still distrustinggovernment and distressing about its natural penchant for corruption andtyranny.[132]

The enabling and disabling aspects of popular sovereignty had a profound impact on Locke’s constitution of structure. Because the legislative, executive, and judicial branches—whether or not popularly elected—each held its political power from the popular sovereign and independently exercised it in trust for the people, each branch had a representational mandate of its own. Equally republican in nature, government institutions were no longer differentiated by either old social orders or even democratically-minded distinctions between elected and unelected officials; rather, the branches were defined solely by functions and personnel.[133] With this new republican, functional separation of powers theory, “modern conceptions of public power replaced older archaic ideas of personal monarchical government.”[134] This theory also got around the problem of how to control the elected legislature and justify public power in less democratically accountable hands. The American articulation of popular sovereignty, then, was the final, crucial step, with which even an unelected judiciary could claim a constitutional responsibility to guard the rule of law and, with it, a power to control (in some way) both the legislative and executive branches.[135]

What all of the above American examples show is that, although Locke originally set out an executive-legislative dualistic structure, the judiciary has historically matured into an independent third branch of government. First, it promotes the constitutional goals of Locke’s structural model, as it further diffuses government power and stands as an additional institutional check upon the other branches. Second, the judiciary has a republican fiduciary trust to uphold the rule of law. It therefore has its own representational mandate, holding its power from and exercising it on behalf of the popular sovereign. Third, although not explored further in this article, courts fulfill this process through the common law processes of adjudication. They resolve particular disputes, apply the laws fairly and equally, treat like cases alike, and ensure that all government institutions and officials act within the confines of their delegated powers. In doing so, courts also confront or defer to the other branches as the public good requires, thus allowing for various degrees of executive discretion as circumstances require (as with legislative deference). Of course, particular legal forms, doctrines, procedures, and remedies can vary from jurisdiction to jurisdiction, and can adapt to emergencies that put them under stress.[136] Still, differences notwithstanding, courts cannot abdicate their fiduciary duty to keep the legislative and executive branches under the rule of law, insofar as possible.[137]

Once brought within Locke’s constitutional model, judicial power is permanently counterpoised against that of the executive. From this position, it can hold the executive legally accountable even for prerogative acts.[138] Of course, the executive might extraordinarily and temporarily act outside of the rule of law or refuse to answer to legal process, in the face of an emergency threatening the existence of the political society.[139] Although unusual circumstances might necessitate such actions, they remain subject to political condemnation or indemnification by the legislature, as well as to legal consequences in the courts.[140] Therefore, the executive can no longer reject or undermine judicial oversight any more than that of the legislature. To do so will break the constitution, violate the public good, and threaten war with the people. Judicial power thus makes it more difficult for the executive to loosen himself from the constitution’s overall structural constraints. The judiciary’s trust to protect the rule of law ensures more checks and warning signs about the dangerous concentration or institutional unaccountability of executive power—a danger that becomes even greater when the executive wields the prerogative.[141] That trust also justifies its opposition, at times, to a virtuous executive with good intentions. In the midst of the Korean War, for example, US President Truman unilaterally ordered the seizure of the steel mills, without any statutory authorization, in order to prevent strikes that might have crippled the American war effort. The Supreme Court declared the order unlawful in Youngstown Sheet,[142] and President Truman complied with the decision. In his concurring opinion, Justice Jackson summed up the perils of executive emergency powers and the importance of legislative and judicial checks to the preservation of liberty. His sentiments traced a lineage back to the constitutional conflicts that had inspired Locke, and his decision instantiated Locke’s political philosophy to reject the president’s sweeping prerogative claims. Citing to England’s Chief Justice Coke and his defiance of the king, Justice Jackson wrote:

The executive action we have here originates in the individual will ofthe President and represents an exercise of authority without law. No one,perhaps not even the President, knows the limits of the power he may seek toexert in this instance, and the parties affected cannot learn the limit oftheir rights. We do not know today what powers over labor or property wouldbe claimed to flow from Government possession if we should legalize it, whatrights to compensation would be claimed or recognized, or on whatcontingency it would end. With all its defects, delays and inconveniences,men have discovered no technique for long preserving free government exceptthat the Executive be under the law, and that the law be made byparliamentary deliberations.

Such institutions may be destined to pass away. But it is the duty ofthe Court to be last, not first, to give them up.[143]