Legal Positivism: Anglo-American Legal Positivism Since H. L. A. Hart

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Hart's Positivism and Dworkin's Initial Objections

Herbert Lionel Adolphus Hart's version of legal positivism, developed in The Concept of Law and refined in the Postscript to the second edition, has been the centerpiece in the development of contemporary legal positivism as well as the focal point of the strongest and most interesting objections to it in the philosophy of law. Hart's own argument builds on the work of positivists who preceded him. In particular, Hart seeks to address and correct the main shortcomings he identifies in the theories of law offered by John Austin and Hans Kelsen. Both Austin and Kelsen thought that laws are a distinguishable subset of norms, identifiable by their possession of an intrinsic and necessary property. In other words, they saw the fundamental project of jurisprudence as determining what it is to be a law. For Austin, laws are orders or commands backed by a threat of sanction issued by a sovereign. The threat of sanction distinguishes a command from a plea or a request while the fact of issuance by a sovereign distinguishes legal commands from all other commands. A sovereign, properly so called, is a person who has secured the habit of obedience from the vast majority of the populace and who is not in the habit of obeying anyone. Like Austin, Kelsen holds that sanctions are both intrinsic to law and necessary for their existence. Unlike Austin, however, he argues that although sanctions are imposed on citizens, legal norms are directives to officials to impose sanctions against citizens in the event that they behave in ways identified as sanctionable by the law.

One of Hart's most important claims is that laws are irreducibly of at least two sorts: (1) power-conferring, or secondary, rules; and (2) primary rules that impose obligations to act or to forbear from acting. Power-conferring rules are not themselves reducible to rules that impose obligations because the failure to comply with a power-conferring rule renders one's action a nullity in law and is neither the basis of liability nor a liability itself. An act nullified is one that does not have the legal effect a successful exercise of the legal power would have produced. A failure to exercise a power according to the required formula is not a failure to comply with an obligation to act or to forbear from doing so. Nullification, in turn, is no sanction. In one fell swoop, then, Hart undermines both the claim that legal rules are of one type and that what is distinctive of the type is the presence of sanctions.

Power-conferring, or secondary, rules are themselves of two kinds: private and public. Private secondary rules empower those governed by law to alter the normative relations among themselves (e.g., as in transferring private property through contracts, marital agreements, and wills) and a legal power to call upon the state's resources to enforce those relations. Public power-conferring rules create and regulate the offices to which legal authority attaches, and their existence is implicated in the very idea of private power-conferring rules as well. For Hart, the most important secondary rule is what he terms the rule of recognition. This rule sets forth the conditions that must be satisfied in order for a norm to constitute part of the community's law and in so doing constitutes an identity condition of a legal system. Beyond that, the rule of recognition both confers a power and imposes a duty on certain officials to evaluate conduct in the light of the norms that satisfy the criteria of law it sets forth.

It is important to Hart's account that rules are expressed in general terms. Such terms possess a core of settled meaning and a penumbra of disputed meaning. This maps on to the distinction between those cases in which no competent speaker of a language can legitimately deny that a rule applies (the core of a rule) and those cases in which reasonable, competent speakers of a language can legitimately disagree (the penumbra). In cases falling within the core of a rule, the law settles the matter and a judge is under a duty to apply the law to the facts at hand. In cases falling within the penumbra of a rule, there is no settled law on the matter and a judge must exercise discretion. The scope of judicial duty is fixed by settled meaning or practice. Where either meaning or practice runs out, judicial discretiona rationally constrained power, not a licenseenters. Some contend that Hart believed that the function of law is to guide conduct by reasons, but this is not his view. Whereas the heart's natural function is to pump blood, the law has no such function. Instead, it can serve any number of human ends and purposessome laudatory and others evil. Hart's view is that whatever business law does, it goes about it by regulating conduct through rules that are reasons. That is its mode of operation, not its function.

For Hart, law is to be understood in terms of its structurein the union of primary and secondary rulesnot in terms of its having a natural function. Thus, Hart's positivism can be identified with the following tenets: laws are rules; legal rules are of two irreducible typespower conferring and duty imposing. Wherever there is law, there is a rule of recognition that sets out the criteria for the laws of a community. That rule is part of the identity conditions of a legal system. All rules are expressed in general terms, and the set of norms that satisfy the criteria of legality are finite. Thus, there will be gaps in meaning and in settled or controlling law. Discretion is inevitable.

Beyond his particular disagreements with them, Hart's positivism shares with its predecessors a view about the relationship between law and morality. This is the view that there is no necessary connection between law and moralitythe so-called separability thesis. Most commentators take the separability thesis to be the sine qua non of legal positivism, but some recent work on legal positivism has raised doubts about the centrality of this claim to the field. Still, there is no denying that Hart was committed to it.

For our purposes, the important features of Hart's positivism are its commitment to judicial discretion and the rule of recognition. The set of binding legal standards in any community is determined by the criteria of legality in that community. Those criteria are set forth in a rule of recognition whose existence and content is fixed by the critical, reflective attitude (the internal point of view) of officialsin particular, judges. The set of standards or rules that satisfy these criteria is finite and thus, in principle, there will be disputes that are not resolved by available legal resources. Judges will be required, therefore, to exercise discretion: a legal power to rely on nonlegal standards, some of which will be moral standards, to resolve legal disputes. This is the so-called discretion thesis.

Dworkin's First Objections

Discretion is inevitable where settled law runs out. It is this feature of Hart's account that Ronald Dworkin exploits and which forms the basis of his first and most famous objections to Hart's account. Cases in which the law runs out are hard cases. Because discretion is a constrained power, judges must decide hard cases by appealing to rationally defensible standards. Ex hypothesi, such standards are not part of the law, but they must be principles or other standards that constitute good reasons or justifications for the decisions a judge reaches at law. Dworkin notes that judges do not act as if the standards to which they appeal in deciding hard cases are optional for them. If we allow, instead, that the moral principles to which judges appeal in deciding hard cases are sometimes legal, binding because they are law, and law because they express an appropriate dimension of morality, one must abandon not only the discretion thesis but the other basic tenets of positivism as wellsuch is the nature of the relations among them.

First, if the moral principles to which judges appeal in hard cases are even sometimes law, then it cannot be true that all laws are rules. Second, if these principles are law, then they are not law in virtue of their satisfying the rule of recognition. They have no institutional source in that sense. This suggests that their legality depends on their content, in particular, on their moral value or worth. But if they are binding in virtue of the fact that they express an appropriate aspect of fairness or justice, then the separability thesiswhich appears to reject the claim that legality can depend on moralitymust be abandoned. So, too, must the rule of recognition, for it is not true that wherever there is law, there is a Master Rule that determines fully a community's binding legal standards.

Exclusive and Inclusive Legal Positivism

Positivists have adopted one of two approaches to Dworkin's objections. Common to both is a willingness to grant one of Dworkin's main premises, namely, that at least in some cases the moral standards judges apply are binding on them, not optional. These approaches differ with respect to the second premise: In virtue of their being binding on officials, are those standards part of the community's law?

Those who reject the second premise are exclusive legal positivists (exclusivists); those willing to accept both premises are inclusive legal positivists (inclusivists, incorporationists, or soft positivists). Though he does not employ these labels, Joseph Raz (1939) is most often cited as the leading positivist of the first sort whereas Jules Coleman (1947) is usually cited as the most prominent advocate of the latter approach. Both approaches reject Dworkin's claim that the binding nature of moral principles undermines positivism, but for importantly different reasons.

Raz emphasizes a significant distinction between a norm being binding on an official (e.g., a judge) and its being binding in virtue of its being the law of his community. Laws of jurisdiction A may, under certain conditions, make laws of jurisdiction B binding on officials in jurisdiction A. That is not enough to make the laws of jurisdiction B laws of jurisdiction A. Understood in this way, Raz's argument is that Dworkin has not made the case that moral principles are part of the law. In fact, however, Raz advances the much stronger claim that if moral principles are binding on officials, they can only bind in the way that norms of other jurisdictions do. This stronger argument relies only on general considerations regarding the relationship between the concepts of law and authority and from no distinctive commitments of legal positivism. Instead, Raz begins with a putative conceptual truth about law: that it necessarily claims to be a legitimate authority. As long as governance by law is not an incoherent idea, then law must be the sort of thing of which the claim to authority could be trueeven if, as a factual matter, it always turns out to be false. This feature of the claim to authority constrains the kind of thing law can be, but the exact constraints it imposes depends on what the claim to being a legitimate authority entails.

On Raz's account, an authority mediates between persons and reasons in such a way that in accepting an authority, an agent is (with rare exceptions) precluded from appealing directly to the reasons that would justify the authority's directives. If one appeals to what Raz calls the dependent reasons in order to identify what the law is or to determine its content, then one vitiates the law's claim to authority. Since the dependent reasons on which law relies and which justify laws are moral reasons, it follows that morality itself cannot be a condition or ground of law. Instead, all law must have what Raz calls a social source. Thus, the claim to authority in conjunction with Raz's theory of authority entails what has come to be called the sources thesis. Some positivists, most notably John Gardner (1965), advance the view that the core of legal positivism is the sources thesis but note that the thesis itself derives from no claim of legal positivism at all. It derives, instead, from the conjunction of a conceptual claim about law and a theoretical and quite general, if controversial, theory of the meaning of authority.

The inclusivist grants both of Dworkin's premises: that moral standards can sometimes be legally binding and that they can sometimes be part of the community's law. His strategy is to show that none of Dworkin's objections to legal positivism are entailed by accepting these two premises.

Coleman argues that it cannot be Dworkin's view that all moral principles are law merely in virtue of their content or moral merits. That would make all of morality part of the law everywhere and always. Put another way, there must be some institutional or social fact that makes some moral principles part of the law in the jurisdictions in which they are law. But then it would have to be that fact that makes them law, not their individual merits. Coleman then argues that there is no reason in principle why the relevant social or institutional fact that renders moral principles law could not be agreement among officials to count those moral principles as law. Nothing in legal positivism, in any case, precludes that.

The Next Phase

It is important to draw a distinction that is rarely explicitly made but which is central to understanding the various current disputes among positivists and between positivists and their critics. This is the distinction between the grounds, or sources of law, on the one hand, and the grounds of the grounds of law, on the other. The grounds, sources, or criteria of law refer to the test for legality within a community. Both the sources thesis and inclusivism are claims about possible constraints on the grounds of law. The sources thesis claims that all such grounds must be social sources; the inclusivist denies that. Dworkin's argument in "The Model of Rules" is that morality can be a ground of law, which is incompatible with the sources thesis and thus with exclusive legal positivism but not with inclusivism.

The fact that inclusivism shares with Dworkin the view that morality can be a source of law has led Dworkin to chide inclusivists, especially Coleman, for having an underdeveloped version of his view. The criticism cuts no ice, however. The core of legal positivism is not a claim about the grounds of law; it is a claim about the grounds of the grounds of law. And on this score, both exclusivists and inclusivists agree that only social factsfacts about individual behavior and attitudecan be the grounds of the grounds of law. What distinguishes positivists from one another is what they take this claim about the grounds of the grounds of law to allow. Inclusivists believe that commitment to social facts at this level does not impose any constraints on potential grounds of law. They hold, moreover, that nothing about the nature of law or authority does either. In contrast, exclusivists hold that facts about the nature of law, in particular its role in our practical lives, imposes constraints on potential grounds of law. Thus, exclusivists accept the sources thesis whereas inclusivists do not. That does not render the inclusivist a proto-Dworkinian.

The sources thesis is said to follow from the conjunction of the claim that law necessarily claims authority in conjunction with a particular account of what that claim requires. In order to escape this implication, the inclusivist might reject the conceptual and/or the theoretical claim, reject the alleged relationship between them, or accept both but deny that they entail the sources thesis. Coleman, for one, rejects both of the premises of the argument, but he is willing to accept them because, he argues, they do not in fact entail the sources thesis.

Roughly, his argument is this: Whereas appealing to the dependent reasons that purport to justify an authoritative directive in order to determine the directive or its content undermines the directive's claim to authority, it does not follow that every moral principle offered as a condition of legality for norms must be among the dependent reasons that justify the particular directive in question. For instance, a clause making equal protection of the law a condition of legality for every putative legal rule need not be a reason that justifies any particular lawone outlawing murder, for example. There is nothing in the logic of law that precludes reasons R1 through R5 being the grounds that justify a law L, but reasons R6 through R9 being the conditions of the legality of L. The mere fact of appealing to moral premises as the conditions of law does not mean that one is appealing to the reasons that would be offered to justify the law.

As Raz characterizes it, the theory of authority claims that one cannot appeal to moral principles to identify the law or to determine its content. This is an epistemic constraint on identifying law and determining its content. But inclusivism is a theory about the grounds of law: the conditions that make law determinate what makes it the law. Inclusivism is, in a broad sense, an ontological or metaphysical theory that may well be untouched by the epistemic constraints that are said to fall out of the appropriate theory of authority.

Dworkin and the Positivists Redux

Dworkin has not been persuaded by either the inclusivist or the exclusivist strategies, but he has focused primarily on the inclusivist strategy. Recall that Coleman responds to Dworkin's objections to Hart by noting that moral facts cannot be law merely in virtue of their being moral facts, for that would render all moral facts legal facts. Instead, the positivist need not deny that moral facts can be legal facts; he need only argue that moral facts are legal facts in virtue of certain legally significant social facts about themtypically acceptance among officials of their status as part of the law. Any such account of the way in which social facts make moral facts part of the law is going to be a form of legal positivism.

Dworkin has responded in two ways: one positive, the other critical. On the one hand, he has developed an argument, expounded primarily in Law's Empire, designed to show how certain kinds of moral facts, not just social facts, turn other moral facts into law. This is his theory of constructive interpretation. On the other hand, he has offered a variety of interesting and important objections to the inclusivist claim that moral facts can be grounds of law and, ultimately, to the claim that they can be grounds of law in virtue of certain social facts or practices.

The point of departure for some of these objections is the idea that morality is inherently controversial, and this fact about it is incompatible with the claim that it can be a condition of legality. At one point, Dworkin argued that positivism holds that the function of law is to guide conduct, in part by resolving disputes and disagreements about what one ought to do. This is one reason for his oft-repeated view that legal positivists identify law with plain or hard factthe sort of thing one could determine with near certitude by looking it up in a book. Morality is too controversial for its inclusion in law to serve this function. This objection has no force. Presumably, one role of morality in our lives is to guide conduct. If morality is capable of guiding conduct, therefore, it is capable of guiding conduct whether it is part of the law or not. Beyond that, nothing in legal positivism would suggest that legal disputes must be resolved in a way that is essentially uncontroversial.

A more serious version of the objection maintains that the essentially controversial nature of morality means that judges applying the criteria of legality that includes morality will often disagree, and this level of disagreement is incompatible with the positivist claim that at the foundation of law resides a social rule, namely, the rule of recognition. A social rule has two dimensions: shared, convergent behavior and a shared critical, reflective attitude toward that behavior. One consequence of allowing that morality might be a condition of legality is widespread disagreement among officials that is incompatible with the requisite agreement necessary for the criteria of law to be determined by a social rule among officials.

Note that the key here is the connection between the grounds of law and the grounds of the grounds of law. If morality can be a condition of legality (a ground of law), as inclusivists claim, then the foundation of law (the grounds of the grounds of law)the rule of recognitioncannot be a social rule. The claim that the grounds of the grounds of law are social facts precludes moral facts from being among the grounds of law. Positivism cannot have it both ways. The problem with this objection is that it treats disagreement about whether the grounds of law are satisfied as if it entailed disagreement about what the grounds of law are. You and I can disagree about whether someone is intelligent while agreeing that we should only hire intelligent people for our company. Disagreement about whether the conditions of legality are satisfied is perfectly compatible with agreement about what those conditions are. If any sort of agreement is required in order for there to be a rule of recognition, it is agreement of the second sort.

At one point, Dworkin responded that all disagreements about whether a rule applies could be formulated as disagreements about what the rule is, thereby raising doubts about whether the distinction Coleman points to between agreement about the criteria and agreement about its applications is helpful. Dworkin's response has proven unpersuasive because it identifies a rule with the set of its instances, which cannot be a plausible understanding of what it is to be a rule. Dworkin eventually adopted a more interesting line of attack, which begins by reflecting on a more general philosophical concern regarding the sort of agreement that is necessary in order for disagreements to make sense; that is, for individuals actually to be disagreeing with one another rather than merely talking past one another. He associates legal positivism with the view that judges and other officials must agree on the grounds of law in order for their disagreements about what satisfies those grounds to be meaningful.

If he has diagnosed the commitments of legal positivism correctly, Dworkin may have identified a powerful objection to it since it appears as if legal positivism cannot explain the possibility of disagreement about what the grounds of law are. Yet such disagreement is a significant feature of legal practice. At bottom, Dworkin has a picture of legal positivism that is very likely warranted by Hart's formulations and much of the positivist literature that has followed. In this picture, legal positivism represents a certain architectural rendering of law and of legal practice. Law is a closed normative system whose boundaries are determined by the scope of agreement. It has a set of initial premises (we can think of these as rules of recognition) whose existence depends on agreement about what they assert or prescribe. Once these rules are in place, we can have a practice called law. These rules make the practice possible and are both inside and outside the practice. They are part of the law, but not, as it were, in the mix. If anything, they are like Carnapian meaning postulates. They are not subject to revision from within the practice; they are immune in that sense. If the practice fails to achieve the aims we have for it, we can change the ground rules and have a new practice. But we do not have a practice that changes from within. We can disagree about what falls within the practice, but we cannot disagree about what the rules are that constitute the practice itself.

Dworkin's most interesting objections to legal positivism can be recast as trying to shed doubt on this architecture of the law. For Dworkin, the fluidity of the boundaries between law and other normative systems, between what is inside and outside law, his deep anti-Archimedianism, are all different ways of getting at the same problem. Dworkin is Willard Van Orman Quine to legal positivism's Rudolph Carnap.

As Coleman and others have argued, the heart of legal positivism is the claim that the grounds of the grounds of law are social factsfacts about behavior and attitudes. It is not obvious that this claim entails either of Dworkin's objections to positivism, namely, the claim that positivism cannot account for disagreement about the grounds of law or the related claim that positivism imposes a Carnapian architecture on legal practice. In fact, the Quinean picture of legal practice is completely compatible with positivism.

Another Picture

If, for the sake of simplicity, we use the term rule of recognition to refer to the grounds of law, then positivism can hold that the rule of recognition is at the center of law, not at the foundation of law. Thus, the rule of recognition is in the mix, subject to revision and even abandonment on the same grounds as are other rules and standards within law. There is a distinction worth emphasizing between the existence conditions of a rule and its revisability conditions. The rule of recognition's special status, moreover, is not a function of it being at the foundation of law but of its inferential importance. Much of the rest of the law of particular communities makes sense inferentially in virtue of the rule of recognition. As the importance of various grounds of law to inferences that warrant other settled areas of the law diminishes, the likelihood of revising that ground of law increases.

Nor is there a distinctive problem in understanding disagreement among participants about the grounds of law, for the rule of recognition is not rigidly fixed by agreement. The complexity of any particular legal practice is likely to mean that there will be different and quite varied views about which putative grounds of law are more or less central to the practice in place.

More importantly, the claim that the content of the rule of recognition is fixed by social facts does not entail that the content of the rule, or its proper formulation, is transparent or otherwise available to officialsthat is, those whose conduct is regulated by it. No more so must the content of the rule be transparent than must the rule governing the use of personal pronouns be accessible to ordinary speakers of a language whose speech it governs. If transparency of the rule to officials is required to coordinate their behaviorand it is an empirical question whether in fact it issharing the rule in the sense Dworkin attributes to positivism is no more than an efficiency condition of law and not a theoretical commitment of legal positivism. There is nothing in the idea that law rests ultimately on social facts that is itself incompatible with disagreement about the grounds of law. Still less does the claim that law is created by social facts alone entail the architectural view of law that renders the grounds of law immune to revision from within.

Positivism need not necessarily be understood in the way sketched here. Rather, the above sketch is designed to suggest only that the social facts thesis does not render positivism vulnerable to the charge that it cannot explain disagreement about the grounds of law. Nor does the social facts thesis leave positivism vulnerable to the charge that it pictures law as shut off from or bounded by other normative systems (other legal systems and other schemes of regulating conduct) in the way the architectural picture of a definite inside and outside of law suggests. Whether this line of argument on behalf of positivism proves ultimately persuasive remains very much an open question.

See also Austin, John; Carnap, Rudolf; Dworkin, Ronald; Epistemology; Hart, Herbert Lionel Adolphus; Kelsen, Hans; Legal Positivism; Quine, Willard Van Orman.


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Jules L. Coleman (2005)