Main source: Duff, Antony, “Theories of Criminal Law”, The Stanford Encyclopedia of Philosophy (Fall 2008 Edition), Edward N. Zalta (ed.), URL = .

The Law’s Voice in the United States

On some accounts, the law is not addressed to the citizens at all: it is, rather, addressed to the courts, laying down what actions they should take (what punishments they should impose, for instance) when certain conditions are satisfied (see Hart 1994: 35-38, on Kelsen). Perhaps the law should also be made known to, or easily knowable by, the citizens on whom it is liable to impinge, as a matter of fairness to them: but they are not its direct addressees. Such a view is no doubt true for some aspects of law, including some aspects of criminal law: laws that deal, for instance, with sentencing, or that define various legal excuses, seem to be addressed to courts rather than to the citizens (on the distinction implied here between ‘rules for courts’ and ‘rules for citizens’ see Fletcher 1978: chs. 6.6-8, 7, 9; Dan-Cohen 1984; Robinson 1997). But it is not a plausible view of law as a whole, or of the central, offence-defining aspects of criminal law in particular: the law speaks to all of us, as citizens. We may hear its voice most loudly, most dramatically, if we find ourselves as defendants in a criminal court, when we are called to answer a charge of criminal wrongdoing, and to hear the law’s condemnation of our conduct if we are convicted: but in defining which kinds of conduct are criminal, and which are legally permissible, the law speaks to all of us, about what we may or may not do. (Some aspects of the substantive offence-defining criminal law are not addressed to all citizens, but only to those engaged in particular activities: only drivers are addressed by most of the road traffic laws, for instance, and only those who deal in shares are directly addressed by the laws concerning insider trading.)

In what tones and terms, then, does or should the criminal law address the citizens? One view, familiar from the classical positivist theories of Austin and Bentham (see The Nature of Law, § 2), tells us that the law, as addressed to the citizens, consists in a set of commands or orders backed by threats to secure obedience from those who might otherwise disobey. The law says to us “Don’t do this!” (or, less frequently, “Do this!”); and if we ask why we should obey that command, the answer will refer either to the law’s authority (“Because it is the law and you ought to obey the law”) or to its power (“Because the law will make you suffer if you do not”)—though for classical positivists like Austin and Bentham the law’s authority seems to reduce to its power. That simple positivist view of law is no longer widely held, but we can see a vestige of it in the very widespread view that the substantive, offence-defining criminal law consists essentially in a set of ‘prohibitions’ (rules that ‘forbid’ certain kinds of conduct), which citizens are supposed to ‘obey’—which, indeed, they supposedly have an obligation to obey.

Now this might indeed be how the law’s voice sounds to those who feel no allegiance to the polity whose law it is, and it is how the law’s voice should sound to those who relationship to it and to the polity is that of oppressed subject to alien sovereign: the law does speak to them in the threatening coercive tones of one who demands, and claims to have the power to exact, their obedience. But it is not how the law should speak to the citizens of a liberal polity (see further Duff 2001: 56-68). As citizens, we are members of the normative community whose values the law purports to express: if it is to address us as citizens, and as responsible agents, it must speak to us not in the peremptory, coercive voice of a sovereign who commands our obedience, but in the rational, normative voice of values which demand our allegiance as the values of our polity. The law of a liberal polity, that is to say, must aim to be a common law: a law which belongs to the citizens, as a reflection of the values they share, rather than a law which is imposed on them by an alien sovereign (compare Cotterrell 1995: ch. 11).

The law, or the legislators who create and declare the law, must claim that there are good reasons to criminalise the kinds of conduct it defines as crimes. Since to criminalise conduct is to declare that it should not be done, that claim must be that there are good reasons why the citizens should not engage in such conduct—reasons reflecting the polity’s values. If the law is to address us as responsible members of the normative political community, it must address us in terms appropriate to those reasons. In the example offered in § 4, I treat my friend as a responsible agent only if the reasons I offer her for going to visit her aunt are of the right kind—the very reasons that, as I see it, make it right for her to do this. Similarly, I am now suggesting, if the law is to address us as responsible citizens, it must address us in terms that appeal to the right kind of reason for refraining from the conduct that it defines as criminal: in terms that appeal, that is, to the reasons which justified criminalising such conduct in the first place.

What kinds of reason could those be? We will return to this question in the following two sections, but should note here that it will be hard to resist the initial conclusion that they must be moral reasons, to do with the moral wrongfulness of the conduct that is criminalised. For, first, the law’s voice is an insistent one. It declares that these things must not be done, even if (it implies) it might suit our individual interests to do them; it attaches significant penalties to the conduct it criminalises: how could such a voice be justified other than by claiming that it is speaking to us of moral duties that we owe to each other and to the polity? Second, the law speaks in terms that appear closely related to the extra-legal languages of morals. It speaks of guilt, of fault, of culpability and wrongdoing; it speaks of murder, rape, dishonesty, theft and the like: unless we are to say that these terms are systematically ambiguous as between their legal and their extra-legal uses (in which case the law would not be making itself accessible or readily intelligible to its citizens), we must conclude that the law’s definitions of offences are meant to be legal definitions of moral wrongs—of kinds of conduct that are wrong either pre-legally, as mala in se are; or as breaches of legal regulations which, once they are created, citizens have a moral obligation to obey (see Green 1997). The criminal law’s definitions of offences will not always aspire to match precisely our extra-legal understanding of the relevant moral wrongs: there will often be good reasons, to do with the practical and moral constraints of law enforcement and the criminal process, for the law’s definitions to diverge from extra-legal moral understandings. But the law’s definitions must be grounded in those extra-legal moral understandings. What the criminal law must say to the citizens is therefore not that they must refrain from such conduct because the law forbids it and can demand their obedience, but that they should refrain from such conduct because it is wrong.

Why should we maintain an institution that speaks to its citizens in such terms of wrongs that should not be committed? Part of the reason is obviously to dissuade the citizens (if they need dissuading) from committing such wrongs—that is the truth in the instrumentalist view. Indeed, nothing said so far rules out the familiar suggestion that a central purpose of a system of criminal law is to reduce the incidence of the relevant kinds of wrongdoing by threatening those who might commit them with punishments that will deter them—whether punishment should be justified as a deterrent is a further issue. But this is not to say that instrumentalists are wholly right, or that Moore is wholly wrong to think that the sole purpose of criminal law is to provide for the retributive punishment of those who culpably commit such wrongs. For, first, even if we are in the end justified in using punishment as a deterrent for those who will not otherwise be dissuaded from crime, the law’s initial appeal to the citizens must be in the moral language of wrongdoing, not simply in the coercive language of deterrence (see Legal Punishment, s. 6): not because such a moral appeal is likely to be instrumentally effective, but because it is intrinsically appropriate to the law’s dealings with the citizens of a liberal polity. Second, we can now plausibly suggest that another purpose of the criminal law is to provide a suitable response to criminal wrongs that are committed. It publicly recognises and condemns them as wrongs by defining them as crimes; it calls those who are alleged to have committed them to account, to answer for that alleged wrongdoing, through a process of criminal trials; it condemns those who are proved to have committed such wrongs by convicting them—and by punishing them, if we understand punishment as involving the communication of censure (see again Legal Punishment, s. 6). The truth in Moore’s view is that such responses to crime are justified not merely as instrumentally efficient means to the reduction of harmful conduct, or to other further ends, but as intrinsically appropriate responses to the kinds of wrongdoing that properly concern the criminal law. We must take such wrongdoing seriously, if we take seriously the values against which it offends, the victim’s standing as one who has suffered such a wrong, and the wrongdoer’s standing as a responsible agent who has done wrong: but to take it seriously is to be prepared to declare it to be wrong it, and to call to account and to condemn those who engage in it.

I have suggested in this section the central purpose of criminal law, as a distinctive kind of law marked out from the other kinds and aspects of law by the features discussed in s. 2, is to define, and to declare the wrongfulness of, certain kinds of wrongdoing, in order not only to dissuade citizens from committing such wrongs, but also to provide appropriate responses to those who commit, or are alleged to have committed, such wrongs. In defining conduct as criminal, the law identifies it as conduct from which we have good reason to refrain, and thus also as conduct for which we will be called to public account, and condemned and punished, if we engage in it. To ask whether we should have a system of criminal law is therefore to ask whether there are kinds of wrongdoing that the state should identify and respond to in such a way—kinds of wrongdoing that the state should take seriously as wrongdoing, and expect its citizens to take similarly seriously.

But what kinds of wrongdoing could these be? We noted that the simple Legal Moralist’s claim, the claim that we have good reason to criminalise any kind of immoral conduct simply in virtue of its immorality, seems implausible. My betrayal of my friend, wrong though it is, does not seem like the kind of wrong that merits public denunciation by the criminal law, or for which I should be called to account by the whole polity through its criminal process; it is, surely, a private matter between me and my friend and perhaps the circle of friends to which we both belong), not a public matter that concerns the state, or my fellow citizens as such.

This natural response to this example points us towards one common way of identifying the kinds of wrong that do properly concern the criminal law—the idea that conduct which is to be criminalised ought to constitute a ‘public’, rather than a merely ‘private’, wrong.
6. Crimes as Public Wrongs

What makes simple Legal Moralism seem implausible is not just the thought that some moral wrongs are not serious enough to attract the attention of the criminal law: though that is true, the wrong I do my friend is not a trivial one—it might destroy our friendship. Nor is it simply the thought that there are very good reasons against criminalising such wrongdoing—reasons that will forcibly strike us as soon as we begin to think how a law criminalising such conduct could be drafted and enforced: Legal Moralists themselves will, as we have seen, argue that such countervailing reasons can often outweigh the reasons in favour of criminalisation; but my example was supposed to make us doubt whether the moral wrongfulness of this kind of conduct constituted any reason at all for criminalising it. The objection to Legal Moralism is naturally expressed by saying that this kind of wrongdoing is a ‘private’ matter that is simply ‘not the law’s business’ (Wolfenden 1957: para. 61).

Must we then reject every species of positive Legal Moralism outright, and insist that the immorality of a kind of conduct is never in itself a good reason for criminalising it? If so, we might still be able to preserve some form of negative Legal Moralism, and hold that conduct that is not immoral cannot properly be criminalised; but we would need to look elsewhere for positive reasons for criminalisation. This, however, seems equally implausible—especially if the argument of the previous section was sound. For I argued there that the criminal law must aim to identify and condemn kinds of morally wrongful conduct, which implies that it is the very immorality of the conduct that gives us reason to criminalise it; and it would anyway be very strange if the reasons for counting such central mala in se crimes as murder and rape as criminal had nothing to do with the moral wrongfulness of such actions. There is, however, a third way between the two extremes of holding that any kind of immorality provides a good reason for criminalisation, and holding that immorality itself never provides a good reason in for criminalisation: we can hold that immorality of the right kind provides a good reason for criminalising conduct that involves it. Moral wrongdoing that could in principle be justifiably criminalised would thus form a subcategory of the larger category of moral wrongdoing.

But how could we identify that subcategory? One familiar slogan is that the criminal law is properly concerned only with ‘public’ wrongs, whereas merely ‘private’ wrongs are either not matters for the law at all, or matters for a civil rather than a criminal legal process (see s.2 above). To gain any help from this slogan, however, we need to know what ‘public’ means in this context, and how to distinguish ‘public’ from ‘private’ wrongs; in the rest of this section, I will explore some suggestions (see also Limits of Law; Lamond 2007).

A pure instrumentalist will of course argue that this is a pragmatic issue: supposing that we do have good reason to criminalise only conduct that is in some way immoral, we decide which kinds of immorality to criminalise, and which to deal with in other ways (or to ignore) by asking which techniques are likely to constitute efficient means to our preferred ends. The range of possible techniques is very wide, even if our only aim was to reduce the incidence of such conduct (which it would not be): extra-legal techniques, such as education, advertising, and situational crime prevention (on which see von Hirsch, Garland & Wakefield 2000); the taxation system (we might as efficiently reduce the incidence of a certain kind of conduct by taxing it as by criminalising it); and the threat of civil liability to pay damages for any harm that was caused. But an implication of the argument of the previous section is that the choice between these techniques should not be a purely pragmatic one: although issues of efficiency are clearly relevant and important, we must first ask which kinds of measure are intrinsically appropriate to the kind of conduct, to the kind of wrong, we are dealing with. We have to ask, that is, whether the conduct in question involves a kind of wrongdoing that merits the public calling to account and condemnation of those who engage in it that the criminal law involves: if it does, we then have at least a good reason to criminalise it; if it does not, we do not. This might be only the first stage in a long and complex deliberation about whether a given type of wrongful conduct should be criminalised, and pragmatic issues would certainly need to loom large in later stages of that process: but my suggestion here is that it is an essential first stage. (Compare the ‘filtering’ model of how we should decide questions of criminalisation offered by Schonsheck 1994. See also Ashworth 2006: chs. 2-3, on the range of ‘principles and policies’ that should bear on questions of criminalisation; and Husak 2007 for a very useful general discussion).

So what should count as a ‘public’ wrong? A first and familiar suggestion, implicit in the way I have talked throughout of criminalising ‘conduct’, is that ‘mere thought’ should not be criminalised: for thought is private; only action or conduct is public. This suggestion captures at least one central aspect of the slogan that criminal liability requires an act (or a ‘voluntary act’, as it is sometimes put), and it does seem to have some force: although mere thoughts can be morally improper (entertaining sadistic fantasies about my opponents, for instance), surely only what actually impinges on our shared social or material world can properly be of interest to the state or its criminal law; but mere thought which is not expressed or acted upon has no such impact. We must note, however, first, that this sets only extremely modest limits on the scope of the criminal law—it does not even protect speech from criminalisation, since speech certainly has an impact on the world. Second, if the ‘act requirement’ is to do any substantive work, we need an account of the concept of ‘action’ or ‘conduct’—an account which will also need to deal with such questions as that of criminal liability for omissions (see Hughes 1958; Feinberg 1984: ch. 4), or for statuses such as being drunk or an addict (see Glazebrook 1978): such an account is notoriously difficult to provide. (For contrasting views on the act requirement see Moore 1993: chs. 2-3; Husak 1998; Duff 2007: ch. 5.)

Within the realm of ‘conduct’ as distinct from thought, and leaving aside the question of omissions, how might we try to identify the subcategory of ‘public’ wrongs? Another familiar suggestion is suggested by Mill’s Harm Principle—“the only purpose for which power can be rightfully exercised over any member of a civilised community against his will is to prevent harm to others” (Mill 1859, ch. 1, para. 9): could we not say that only conduct that wrongfully harms or threatens to harm others is a suitable candidate for criminalisation; that the criminal law is properly concerned only with harmful immorality? This leads us into some notoriously difficult questions: for instance, about whether the paternalist criminalisation of conduct that harms only the agent can ever be justified (see Feinberg 1986); about whether we might also have reason to criminalise conduct that, though it does not cause harm, is seriously offensive to others (see Feinberg 1985; Simester& von Hirsch 2006); about whether there are kinds of immorality so gross that, even if they cause no harm, we have reason to criminalise them (see Feinberg 1988; Dworkin 1994). We also need an account of the concept of harm itself, which raises further problems (see e.g. Kleinig 1978; Feinberg 1984; Raz 1986: ch 15, 1987). For instance, can we plausibly so define ‘harm’ as to rule out the argument that any immoral conduct is itself harmful, either to those whom it wrongs (since I am harmed by being wronged), if it does wrong anyone, or by doing moral harm to the society or culture in which it is done (see Devlin 1965; Dworkin 1994)? Can we so define ‘harm’ as to exclude purely trivial wrongdoings from the scope of the criminal law, for instance by focusing on setbacks to ‘welfare interests’ (Feinberg 1984: ch. 1)? We cannot pursue these issues here, but we should note two ways in which the Harm Principle fails to set any very tight constraints on the scope of the criminal law (see generally Holtug 2002; Duff 2007: ch. 6).

First, as I expressed the principle, it allows the criminalisation of conduct that threatens, as well as conduct that actually causes, harm. Even the more limited category of conduct that causes harm becomes problematic when we ask what counts as causing harm (see von Hirsch 1996): our existing laws criminalise not only conduct that immediately causes harm, but also kinds of conduct whose causal relationship to the harm is more remote—for instance conduct that enables or assists another’s commission of a crime; so we need to ask how far we should extend the law’s reach in this direction. The problems multiply when we turn to conduct that, whilst it does not actually cause harm, is criminalised because it threatens harm, or creates a danger of harm: to the broad category of ‘nonconsummate’ offenses (see Husak 1995). This category includes conduct that is intended to cause harm (attempts to commit crimes, for one obvious instance); conduct that, though not intended to cause harm, recklessly or negligently endangers others (dangerous driving, for instance, or breaches of health and safety rules); and conduct that, although it might not itself be dangerous, is of a kind that is usually dangerous (speeding, for instance). Again, we need to ask how far the criminal law should reach in this direction (see Harcourt 1999; also Dubber 2001).

Second, even if we limit our attention to conduct that obviously and directly causes what must surely count as non-trivial harm, not all such conduct seems even in principle to be apt for criminalisation. The friend whom I betray would surely count herself as seriously harmed by my betrayal; someone whose spouse betrays their marriage by committing adultery might reasonably claim to be seriously harmed by that betrayal. But we should not therefore see any good reason to criminalise betrayals of friendship; and although adultery is indeed a crime in some states, arguments about whether it is in principle apt for criminalisation do not typically depend on claims that it is, or is not, harmful to the betrayed spouse—the reality of that harm is taken for granted. Nor will it help to suggest, for instance, that the kinds of wrongful harm that are apt for criminalisation are those and only those that set back ‘welfare interests’ (see Feinberg 1984: 37-38, 61-63): if our welfare interests concern those goods that constitute the ‘basic requisites of [our] well-being’ (Rescher 1972: 6, quoted approvingly in Feinberg 1984: 37), they surely include such goods as friendship and other loving relationships.

So even if the Harm Principle can do some substantial work in limiting the proper scope of the criminal law, it does not take us far enough, since there are kinds of seriously harmful conduct that we do not think should, even in principle, be criminalised.

Perhaps, if crimes are ‘public’ wrongs, we should now distinguish within the category of wrongfully harmful conduct between public and private harms: the betrayal of a friendship or a marriage is not apt for criminalisation if and because it causes only private harm. But what is to count as a public harm, or public wrong?

On one familiar reading, a wrong or harm is ‘public’ if and because it affects, i.e. wrongs or harms, ‘the public’, rather than only an individual victim (see Blackstone 1765-9: Bk. IV, ch. 1, 5); wrongs or harms that affect only individual victims are—if they are matters for the law at all—appropriately pursued by those individual victims through the civil courts.

We can understand some crimes as harming or wronging ‘the public’—‘the public’ being understood either a set of individuals among whom we cannot identify determinate individual victims, or as a collectivity with shared goods that crime impairs. Three examples will serve to illustrate this point.

First, ‘public order’ offences involving violent, riotous conduct are injurious to the public in that they pose a threat of serious harm to any of the indeterminate number of individuals in the area, and might threaten to undermine that shared sense of assured security on which our civic life depends. (Compare Braithwaite & Pettit 1990: 60-68, on ‘dominion’ as the central civic good. There is of course enormous scope there is for the political abuse of public order laws—see Lacey et al 2003: ch. 2; but our concern here is with the issue of whether we have any in principle reason to define a category of public order crimes.) Similarly, offences of endangerment that involve no ‘disorder’ (driving offences which endanger other road users generally, for instance, and offences involving public health and safety) often threaten the public, rather than determinate individuals.

Second, some crimes attack or threaten the polity’s own institutions, and thus threaten or harm ‘the public’ as a collectivity. This category includes such crimes as perjury, attempts to pervert the course of justice, the offering of bribes to, or their acceptance by, public officials, and various kinds of electoral malpractice. In some such cases a determinate individual might be wrongfully harmed—an innocent person might be wrongly convicted, or might lose a civil case, because a witness commits perjury: but whether or not we can identify any such individual victim, the crime attacks a public institution which is crucial to the public interest.

Third, other kinds of wrongful conduct are apt for criminalisation because they involve serious unfairness towards one’s fellow citizens. Someone who evades their taxes might cause no identifiable consequential harm, either to any individual or to the social institutions which are funded by taxation; if asked to explain the wrong she commits, we would appeal to some version of ‘What if everyone did that?’, rather than trying to identify any consequential harm that she causes. We would appeal, that is, to the unfair advantage that she takes over all those who pay their taxes: she gains the benefits that accrue to all citizens from the taxation system, but refuses to make her appropriate contribution to that system.

So we can explain why some kinds of conduct are properly criminalised by showing how they wrong or harm ‘the public’, or ‘the public interest’: but can we explain all crimes in this way? Can we sustain the general claim that conduct should, in principle, be criminalised only if and because it wrongs or harms ‘the public’ in this sense? There are two ways in which we might try to do this—by appealing either to the idea of public order and stability, or to that of unfairness.

Consider, first, the idea of public order, and the suggestion that the criminal law’s proper purpose is to protect the “smooth functioning of society and the preservation of order” (Devlin 1965: 5). We find relatives of this suggestion in Becker’s argument (1974) that the criminal wrongfulness of crimes consists in their tendency to cause ‘social volatility’, and in Dimock’s argument (1997) that it lies in their tendency to undermine the kinds of trust upon which civic life depends. What makes crimes—including such crimes as murder and rape—wrongful in a way that properly concerns the criminal law is, on such accounts, not the wrongful harm that they do to their immediate individual victims, but their wider effects on social stability or trust.

Consider second the idea of unfairness. According to one well-known theory of punishment (see Murphy 1973; Dagger 1993), crimes deserve punishment because the offender takes an unfair advantage over all his law-abiding fellow citizens: he accepts the benefits of their law-abiding self-restraint (the mutual security provided by an effective system of law) but refuses to make his proper contribution to that system by exercising such self-restraint himself. Might we ground a theory of criminalisation on such a theory of punishment? We should criminalise murder, rape and other central mala in se because, apart from the wrongful harm that they do to their individual victims, they wrong ‘the public’ (the generality of law-abiding citizens) by taking unfair advantage of them.

The obvious objection to such ways of explaining the idea of crimes as public wrongs or harms is that, precisely by portraying crimes as wrongs done to ‘the public’, they distort their character as wrongs that merit criminalisation. We are now to criminalise murder or rape, not because of the wrongs that they do to their individual victims, but because of their effects on social stability or trust, or the unfair advantage they take over the law-abiding; from which it follows, if the criminal law should address the citizens in terms of the reasons and values that inform its definitions of crimes (see s. 5 above), that a murderer or rapist is to be condemned and punished not for what he did to his individual victim, but for acting in a way that created social volatility, or undermined trust, or took unfair advantage over his law-abiding fellows. This is surely not how we should understand the criminal wrongfulness of such crimes.

To illustrate this point, consider the example of domestic violence and abuse. In English law intra-marital rape was recognised as a crime only in 1991 (see R [1991] 4 All ER 1981); until then, a husband who forced sexual intercourse on his wife without her consent was not guilty of rape. Similarly, although domestic violence (typically husbands violently beating up their wives) was formally speaking a crime, it was often not taken seriously as a crime by the criminal justice system: the police were often unwilling to intervene in ‘domestic disputes’ or to prosecute domestically violent men, seeing it rather as an issue for the couple to work out for themselves. No doubt part of what lay behind these practices was a view that the wrongs being done were, if wrongs at all, not that serious; but we can also discern the view that these were ‘private’ rather than ‘public’ wrongs. If we then ask what justified the change towards recognising intra-marital rape as genuine, criminal rape, and domestic violence as a genuine crime that should be prosecuted, it is not plausible to answer in terms of either of the accounts noted above. It would not be plausible to argue that domestic violence or intra-marital rape is liable to create social volatility (indeed, such crimes are often committed by men who in their lives outside the home are models of peaceful conformity); or that it undermines the kinds of trust on which social life depends (such crimes, if confined to the home, do not undermine the trust that we can have in our dealings with strangers, which is the kind of trust that is relevant here); or that it takes unfair advantage over all those law-abiding people (or men) who refrain from these or other kinds of crime—as if the law-abiding would love to commit such wrongs if only they were not restrained by the demands of fairness.

To explain why such domestic abuse should be criminal, and taken seriously as criminal, we must look not for some ‘public’ harm or wrong that it involves distinct from the wrongful harm it does to its individual victims, but at that wrongful harm itself. What matters is that we come to see the wrongs suffered by abused wives not just as their private business, but as our collective business as citizens of a polity to which we belong with them; we come to recognise that they have as strong a claim to the protection and support of their fellow citizens as do the victims of attacks by strangers—a claim grounded simply in their fellow membership of the polity, as our fellow citizens. The wrongs done to them are ‘public’ wrongs not because they wrong the ‘public’, but because they are wrongs that properly concern the public—their fellow citizens; even when they are committed in what might count, empirically, as ‘the privacy of the home’, they belong in what should count, normatively, as the ‘public’ realm. We could then also say, if we wish, that such wrongs are wrongs against, or injurious to, the public—the polity and its members: they implicitly deny the core values by which the polity defines itself, and the basic normative bonds by which we define our civic relationships with each other; they are wrongs not just against their individual victims, but against all of us insofar as we identify with those victims as our fellow citizens—they are wrongs in which we collectively share, and which we make ‘ours’ (see Marshall & Duff 1998). But to talk in this way of ‘public’ wrongs or injuries is not to try to ground the claim that such wrongs should be criminal: the appeal to the idea of a ‘public’ wrong now expresses, rather than trying to ground, the claim that it is a wrong that concerns us all, and that is therefore apt for criminalisation.

If that is right, however, we cannot look to the idea of public wrongs or harms to provide criteria or principles of criminalisation. We can say that the criminal law should be concerned with ‘public’, rather than ‘private’, wrongs, but that is because to call a wrong ‘public’ in this sense is already to class it as a kind of wrong that is apt for criminalisation—a kind of wrong which should be publicly denounced and whose perpetrators should be publicly investigated, prosecuted, condemned and punished; a kind of wrong whose perpetrators should be called to account by the polity as a whole, not just by the individual victim.

The upshot of this section is that we still lack any clear criteria or principles by appeal to which we can try to determine which kinds of conduct should be criminal. However, though this might be frustrating, we should at least by now be clearer about what kinds of claim we must be able to make about kinds of conduct that we want to show are apt for criminalisation. First, we must be able to show that and how they involve wrongdoing: for as we saw in s. 2, the criminal law focuses on wrongs that should be condemned, rather than just on harms that need to be repaired or compensated; and as we saw in s. 5, the criminal law must speak to us of wrongs that we should not commit. Second, we must be able to claim that the wrong is of such a kind that it should concern us all as citizens—we should not leave it to the individual victim to pursue, or not to pursue, a civil case against the wrongdoer. I have not suggested determinate criteria by which we can identify such wrongs, nor do I think that any determinate criteria can be provided; although theorists might yearn to find a single principle, or a single set of principles, by reference to which we could determine the (in principle) proper scope of the criminal law, such yearnings are doomed to be frustrated (for two recent examples, see Dan-Cohen 2002, Ripstein 2006; for critical discussion see Duff 2007: 138-9; Husak 2007). We can, however, identify the main kinds of consideration that should be relevant. Is the wrong one that injures ‘the public’ rather than any individual victim? Is it one that flouts or implicitly denies the core values by which we define ourselves as a polity, and which supposedly underpin our civic relationships? Is it one from which we should be able to expect the protection of our fellow citizens (which is to ask whether it is a wrong from which we should be able to expect to be categorically safe as we go about our normal lives, rather than a kind of wrong that we can be expected to risk on condition that we can seek compensation if we suffer it)? Answers to these questions will be contestable, and will properly emerge only from a collaborative attempt to understand what joins us as citizens and what we owe to each other as citizens—an attempt which will lead to different results in different political communities: but we have made progress if we have at least identified more clearly the questions that we must ask.