DETERMINISM & CRIMINAL RESPONSIBILITY

The American criminal justice system is based on the notion that individuals are responsible for their actions and can be punished when they choose to violate societal standards. Thus it is said to be rooted in the concept of “free will.” If all human actions and choices are caused by factors beyond the actor’s control, and is therefore morally excused, then that action or choice should not be legally punishable. This leads to the absurd conclusion that no actions or choices should be legally punishable.

Criminal liability follows from a determination that an actor engaged in criminal conduct by inquiring (1) did the defendant voluntarily engage in proscribed conduct (actus reus), and (2) if he did, was he aware of the circumstances that made his conduct criminal (mens rea)?   Actus reus and mens rea include the presumption that individuals are responsible agents capable of making choices and intending the natural consequence of their acts. “Voluntarily” implies that an individual exercised his free will in doing the act, or that he could have done otherwise.

It is helpful in discussing the relationship between criminal law and behavioral genetics to distinguish between the broad concept of free will (“theoretical free will”) and “legal free will.”   Theoretical free includes philosophical, metaphysical, psychiatric, and biological perspectives on the subject. Legal free will is simply based on the presumption that individuals actively choose to engage in criminal conduct.  Legal free will theory contends that human behavior in a given situation is the result of individual choices made by autonomous actors.  It assumes that individuals have the inherent ability to choose or choose not to act in a certain way.  Human choice is fundamental to the operation of the system of laws, a necessary presumption to foster better social relationships.  This is based on the belief that social systems are strengthened by holding people responsible for their conduct.   Legal free will is value preference; it exists along with causal agents.

Our criminal justice system is an “excusing system.”  In addition to the requirement of a certain mental state (mens rea) such an intent, purpose, knowledge, recklessness, or negligence, our system recognizes certain excuses from criminal liability. The generally recognized excuses are mistake, accident, provocation, insanity, and duress.   An excuse says that even though I did the act, I am not culpable because some disability in my freedom to choose the right thing makes it inappropriate to punish me.

Excuses focus on the actor and his subjective mental state.   Excuses are different from justifications used to avoid criminal responsibility, such as self-defense.   Justifications entitle others to act in the same way under similar circumstances.   Excuses do not make an act any less wrongful, and therefore do not create an entitlement to act in a certain way.   The question raised by determinism is whether predispositions to engage in behavior that society has declared criminal resulting from genetic or other biological factors should serve as an excuse to criminal liability.

Because full determinism and application of the causal theory of excuse lead to the absurd result of no responsibility, the concept of “degree determinism” is used to allow acceptance of determinism as well as criminal responsibility.  Degree determinism holds that all human conduct is not fully caused; that varying degrees of determinism and free will exist in all actions on a continuum from freedom to causation.  Thus the question becomes at what point on the continuum does human behavior become so determined that the actor lacks choice and thus his actions are not blameworthy?

The one biologically based defense recognized as a defense to criminal responsibility is insanity.   The defense is limited, however, to medical proof that a defendant suffered from a mental illness or defect.   Courts reject claims of mental illness based on a genetic predisposition, generally on the basis that the defendant can appreciate the wrongfulness of his act notwithstanding any genetic predisposition.

Defendants have offered a variety of defenses based on biological deficiencies, including genetic deficiency, automatism, amnesia, Post-traumatic Stress Syndrome, premenstrual syndrome, along with severe environmental deprivation and battered woman’s syndrome, and recently “affluenza,” the defense that a teenage defendant was unable to understand the consequences of his actions because of his financial privilege. Defendants have argued that their acts were not voluntary, in that because of a genetic predisposition to addiction, violence, impulsivity, or other biological trait they did not exercise free will, but were compelled to act. These attempts have been generally unsuccessful.  Courts seek a causal link between an asserted behavioral predisposition and the criminal act, and they are unwilling to accept statistical data when considering whether that link exists for a specific act.  

Defendants generally have used behavioral predisposition arguments in the sentencing phase rather than in the guilt phase of a trial, arguing that their genetic makeup or socio-economic background is a mitigating factor in their culpability.  This is a double-edged sword, however, for courts can use the behavioral disposition as an aggravating, as opposed to mitigating, factor in sentencing.