Justification: Theory

To approach the theory of justification, one needs first to understand what a justification is. A justification renders a nominal violation of the criminal law lawful and therefore exempt from criminal sanctions. For example, if the force used in self-defense against an aggressor is both necessary and reasonable, injuring the aggressor is justified and therefore lawful. Those who act in justifiable self-defense exercise a privilege and act in conformity with the law.

Claims of justification should be distinguished from two other bases for claiming that conduct is not subject to criminal liability. First, someone might argue that his conduct falls wholly outside the criminal law. Killing a fly violates no prohibition of the criminal law; it therefore requires no justification. Killing a human being, intentionally or negligently, does violate a prohibition and therefore the conduct requires a justification to be lawful. Thus, one must distinguish between conduct that violates no general norm (killing a fly) and conduct that nominally, but justifiably, violates a valid prohibition of the criminal law (killing an aggressor in self-defense). A justification concedes the nominal violation of the prohibitory norm but holds that the violation is right and proper.

A claim of justified violation should also be distinguished from the assertion that prohibited and unjustified conduct is excused by virtue of circumstances personal to the accused. The defense of insanity, for example, does not seek to justify the violation of a norm. Rather, the defense concedes that the violation is unjustified, but seeks to exempt the particular actor from responsibility for the unjustified act. A claim of justification maintains that the act is right; a claim of excuse concedes that the act in the abstract is wrong, but argues that the actor is not personally responsible for having committed the act. Injuring an innocent person is wrong, but if the actor is insane, his condition precludes his being held responsible for the wrongful act.

Thus, the issue of justification appears as the second in a set of three ordered questions bearing on criminal liability: (1) Did the suspect's act violate a valid norm of the criminal law? (2) Is the violation of the norm unlawful ( justified)? (3) Is the actor personally accountable for the unlawful violation; that is, is the unlawful violation unexcused? A negative answer to any of these three questions terminates the inquiry into liability.

In addition to its function as the second stage in this scheme for analyzing liability, the concept of justification enters into the analysis of several specific legal problems. Western legal systems generally assume, for example, that self-defense is permissible only against unlawful attacks. Because the justified use of force is lawful, self-defense is unavailable against justified force. A police officer's use of necessary force to effect a valid arrest is justified; therefore, the person arrested cannot invoke self-defense to justify forcible resistance to the arrest. In contrast, the excused use of force—by an insane assailant, for example—remains unlawful. Self-defense is therefore permissible against an excused aggressor (Model Penal Code §§ 2.04, 2.11 (1)).

Of course, the law could shift its stand on self-defense so that both justified and excused attacks, or perhaps neither, triggered the right to use force in self-defense. So long as the law and our judgments of just liability remain as they are, however, we shall have to attend to the distinction between justified attacks, which undercut the right to respond with defensive force, and excused attacks, which permit self-defense in response.

Theories of complicity that distinguish between perpetrating an offense and merely aiding another's offense also require attention to the distinction between justification and excuse. Justified conduct no longer qualifies as an offense, but excused conduct might well be though of as an excuse for these purposes. If someone shouts encouragement to an aggressor later to be found insane, is the party shouting encouragement liable for aiding and abetting the offense? If the excused aggression is regarded as no offense at all, then it is difficult to regard the shouting as punishable assistance. How, after all, can one be liable for assisting that which is not a crime? On the other hand, if the assault by the insane actor is regarded as an excused offense, the party aiding the offense could be liable on the basis of his own unexcused aiding of the unlawful assault.

The law of complicity could conceivable be altered so that the party shouting encouragement would be liable as an accomplice regardless of whether the aggression encouraged is excused or justified. Section 2.06(2)(a) of the Model Penal Code seems to effect this alteration by suggesting that an insane perpetrator should be treated as an "innocent or irresponsible agent" in the hands of those aiding and directing him. This section requires, however, that for the party shouting encouragement to be liable, he must "cause" the insane assailant to engage in the assault. For encouragement to qualify as control or causation, the law would have to settle for a diluted conception of causation, which could give rise to problems in other areas. A less troublesome approach would be to treat the concept of offense as dependent solely on the commission of an unlawful (unjustified) act. Thus, the party shouting encouragement would be liable not for causing an innocent person to act, but for aiding in the commission of an offense by the excused aggressor (Model Penal Code § 2.06(3)(a)).

The concept of justification enjoys, therefore, a distinctive place in the structure of criteria bearing on criminal liability. Of course, skepticism remains possible as to whether working out the three dimensions of criminal liability (prohibited act, justification, excuse) aids one's understanding of criminal liability and contributes to a just resolution of disputed issues. The analysis of self-defense and complicity seems to require attention to the distinction between justification and excuse. Other issues, discussed below, are clarified by the distinction between committing a prohibited act and justifying the prohibited act.

This article considers several theoretical and controversial quandaries that attend the analysis of justificatory claims. First, which issues and defenses in the criminal law are properly regarded as claims of justification? Second, what are the general criteria of justification? Third, what are the respective roles of the legislature and the judiciary in developing claims of justification?