Paul H. Robinson—Criminal Law Defenses: A Systematic Analysis

     Unlike many aspects of criminal law, defenses have not yet been the subject of comprehensive conceptual analysis. The general nature and scope of most defenses have been perpetuated for centuries with little or no question. Current debates commonly focus on whether a particular defense should apply in a particular circumstance, but rarely consider the larger perspective. How do circumstances covered by one defense compare with those of other defenses? Do defenses overlap? If so, will the outcome in identical situations vary with the defense asserted? Should it? Are there gaps between defenses, that is, circumstances in which our common sense of justice suggests that the defendant should be exculpated, yet where no defense applies? Do defenses based on theoretically analogous grounds of exculpation generate analogous results? The general inquiry, which seems never to have been undertaken, is: how does the collection of recognized defenses operate as a system? * * *

     There are, no doubt, many people who believe that defenses defy such systemization. Defenses, it might be argued, are the embodiment of such complex human notions of fairness and morality, tempered by the demands of utility and efficiency, that they are too complex and perhaps too illogical to be reduced to an integrated, comprehensive, and internally consistent system of exculpation. * * * 

     This article attempts to provide some measure of conceptual organization for criminal law defenses * * *.

I.   A System of Defenses

     The term “defense” is commonly used, at least in a casual sense, to mean any set of identifiable conditions or circumstances which may prevent a conviction for an offense. * * * Upon examining the functions of and the rationales supporting these rules and doctrines, five general categories become apparent. They may be termed: failure of proof defenses, offense modification defenses, justifications, excuses, and nonexculpatory public policy defenses. * * *

1.       Failure of Proof Defenses

     Failure of proof defenses consist of instances in which, because of the conditions that are the basis for the “defense,” all elements of the offense charged cannot be proven. They are in essence no more than the negation of an element required by the definition of the offense. * * * 

     Mistake provides a clear example * * *. Assume, for example, that incest is defined as having intercourse with a person the actor knows to be an ancestor, descendant, or sibling. If the actor honestly believes that the person with whom he is having intercourse is not a relative, one might term his mistake a “defense.” In reality, the actor’s mistaken belief prevents a state from proving the required mental element of knowledge of the familial relationship. When this sort of mistake of fact is recognized as a “defense,” it is considered not a general mistake excuse, but only a failure of proof defense. * * *

2.       Offense Modifications

     Offense-modification defenses are real defenses in the sense that they do more than simply negate an element of an offense. They apply even where all elements of the offense are satisfied. They are distinguishable from general defenses (like self-defense or insanity), however, because they introduce criminalization decisions similar to those used in defining offenses, rather than giving effect to general principles of exculpation. They provide a more sophisticated account, when needed, of the harm or evil sought to be prohibited by the definition of the offense.

     A parent, against the advice of police, pays a $10,000 ransom to the kidnapper of his child. A businessman pays monthly extortion payments to a racketeer. These persons may well satisfy the elements required for complicity in kidnapping and extortion, yet they will nonetheless have a defense to these charges. * * *

     There is a single principle behind these modifications of the definition of an offense: while the actor has apparently satisfied all elements of the offense charged, he has not in fact caused the harm or evil sought to be prevented by the statute defining the offense. * * *

     In many cases, the defenses of this group are given no formal name but exist only as accepted rules. For example, with regard to the kidnapping and extortion examples above, a common rule provides that the victim of a crime may not be held as an accomplice even though his conduct has in a significant sense aided the commission of the crime. * * *

      Some offense modifications are considered defenses, rather than simply rules or doctrines, but they operate similarly to modify the definition of offenses. * * *

     Offense modifications, like failure of proof defenses, commonly apply to only one specific offense. * * *

3.       Justifications

     Unlike failure of proof and offense modification defenses, justification defenses are not alterations of the statutory definition of the harm sought to be prevented or punished by an offense. The harm caused by the justified behavior remains a legally recognized harm that is to be avoided whenever possible. Under special justifying circumstances, however, that harm is outweighed by the need to avoid an even greater harm or to further a greater societal interest.

     A forest fire rages toward a town of 10,000 unsuspecting inhabitants. The actor burns a field of corn located between the fire and the town; the burned field then serves as a firebreak, saving 10,000 lives. The actor has satisfied all elements of the offense of arson by setting fire to the field with the purpose of destroying it. The immediate harm he has caused—the destruction of the field—is precisely the harm which the statute serves to prevent and punish. Yet the actor is likely to have a complete defense because his conduct and its harmful consequences were justified. The conduct in this instance is tolerated, even encouraged, by society. * * *

4.       Excuses

     Excuses, like justifications, are usually general defenses applicable to all offenses even though the elements of the offense are satisfied. Excuses admit that the deed may be wrong, but excuse the actor because conditions suggest that the actor is not responsible for his deed. For instance, suppose that the actor knocks the mailman over the head with a baseball bat because she believes he is coming to surgically implant a radio receiver that will take control of her body. The defendant has satisfied all elements of the offense of aggravated assault—she struck the mailman with a deadly weapon with the purpose of causing him bodily injury. This is precisely the harm sought to be prevented by the statute, and it is not outweighed by any greater societal harm avoided or greater societal interest furthered. It is conduct that society would in fact condemn and seek to prevent. The defendant is exculpated only because her condition at the time of the offense—her paranoid delusion—suggests that she has not acted through a meaningful exercise of free will and therefore is not an appropriate subject for criminal liability. * * *

5.       Nonexculpatory Public Policy Defenses

     In 1971 an actor forcibly took a wallet from an old man at gunpoint. The crime goes unsolved until 1978 when he is identified and arrested. Although he committed the offense, caused the harm sought to be prevented by the statute, and has no claim that his conduct is justified or excused, the actor may nonetheless have a defense. The statute of limitations may bar his conviction for robbery despite his clear culpability because by foregoing that conviction society furthers other, more important, public interests.

     Time limitations on criminal prosecutions are often supported as fostering a more stable and forward-looking society. * * * These rationales may justify current statutes of limitations, but it must be noted that they are not based on a lack of culpability of the defendant. They are purely public policy arguments. * * *

     Other public policy-based bars to prosecution include diplomatic immunity, judicial, legislative, and executive immunities, * * * and incompetency. Each of the * * * forms of immunity furthers important societal interests * * *.

     This balancing of countervailing public policy interests, both societal and personal, should be distinguished from the balancing which occurs in justification defenses. In the latter, the harm done by the defendant's act is outweighed by the societal benefit that it creates, and as a result, he is not blameworthy. In nonexculpatory defenses, the defendant’s conduct is harmful, and creates no societal benefit; the defendant is blameworthy. The societal benefit underlying the defense arises not from his conduct, but from foregoing his conviction. The defendant escapes conviction in spite of his culpability.