Assumption #1: There is no free will - all of our decisions are all determined by the causal web of biology and environment.*
(*note: determinism will heretofore be defined in the context of human consciousness outcomes, such that human thought be considered determined by events beyond one's control, even if other, non-strictly-deterministic forces may be at work at the atomic or super-atomic level.)
Our modern concept of justice is somewhat nebulous. At its root, it is based on an empathetic response. We identify with the victim and their suffering, and we then lash out instinctively, as if it were us that was threatened. This is justice of the moment, and is as simple as self-preservation. As an empathetic extrapolation to broader society, this puts in place systems of physical response (police, army, etc.) and systems of imprisonment, both of which provide direct protection from crime, and also a measure of deterrence for would be criminals. These are obvious measures and one of the basic premises for civilization itself.
A third function of our justice system is the prospect of rehabilitation. This is controversial for a number of reasons, a good portion of which depends upon the very subject of this article: the concept of free will vs. determinism. As its efficacy is frequently debatable, and requires extra resources to provide, rehabilitation must make the case not only that it works, but that the criminals are worthy of such social investment. Assuming for the moment that a certain method is effective, the question then becomes down to the generosity of the public to pay for it. At this point one can still believe in free will and find two reasons for merit in rehabilitating criminals.
The first is practical: it eliminates recidivism, and thereby future threat. The second is more spiritual, or intuitive in nature. As a Judeo-Christian concept, forgiveness has a long (although rocky) history. But it is safe to say that it thrives in the following of standard church doctrine across the West. In a secular sense, whether as a direct extension of this dogma, or simply as an outgrowth of psychological development, the concept of forgiveness is also a powerful force as it appeals to the idea that people can change and feel remorse for their crimes. Social logic tells us that the promotion of peaceful behavior in the individual has a direct impact on society as it acts as an example of positive behavior, promoting peace and safety for the group. As a description of socialization, this is also an argument for determinism, yet it could be seen as having a minimal impact, and thus of little consequence for the free application of will. However, this leads us back to the degree to which denial of determinism influences one's interest in rehabilitation to begin with: if one considers will independent of such things as peer influence, then the socializing impact of rehabilitated criminals is limited.
Finally, and least quantifiably, our justice system seeks to provide a "sense of justice" to the victim (whether an individual or society at large). This "sense" of justice serves a powerful social purpose, and is universal enough to be considered a possible evolutionary trait. To the extent that it defines crime, it offers society a model for what and what not to deem acceptable.
Beyond this establishment of a criminal model, however, the "sense" of justice is also thought of as providing a sort of emotional compensation to the victim. Whether it actually accomplishes this goal is certainly a difficult proposition, as it depends upon what justice ultimately means in an intuitive, emotional sense. Does it require suffering on the part of the perpetrator - and if so, according to what metric? Does it require that they repent and truly feel remorse for their crimes? Should they be required to "repay" some level of debt to society?
And how so (again, by what metric)? And lastly, society's "sense" of justice must be different than that of the individual. It is a commonly held conviction that, were a serious enough wrong be committed against a loved one, personal vengeance would be seriously considered. And the more heinous the crime, the more violently passionate the response.
This threat response is obvious when the danger is to one's self or close family and friends. Yet as the circle of familiarity widens, the threat response diminishes. Modern society however, through various social institutions allows us to attach ourselves ever further, to identify more closely, to distant people. The most obvious instance of this is the rather arbitrary standard we apply to threats faced by our nation's citizens. As we identify as citizens of a particular country, we place a higher value on that citizen's well-being. Another example would be perception of harm to begin with, as in the case with abortion. Those who view fetuses as full human beings, and thus identify with them, feel personally attacked by abortion.
So what role does determinism play in justice? As a practical matter, in the sense that a definition of crime is established and sought to be prevented, it is irrelevant. But to the extent that the criminal's motivation is brought in to the equation, its implications are profound. Determinism demands that we radically alter, or at least impose an entirely new set of controls on our fundamental nature as humans. As noted, we have a strong impulse for vengeance, likely biological in nature, but certainly affected by cultural disposition. Yet this impulse is strongly dependent upon how we view the perpetrator.
To illustrate, consider the difference between a natural "disaster" and a human act of violence. Were a tree to fall on one's home, killing a member of their family, despite intense suffering over their loss, the concept of vengeance, or "justice" applied to the tree would be absurd. However, absurd as it may be, the human impulse is still active - who among us has not stubbed their toe on some piece of furniture and not cursed it in a fit of pain-induced delirium? Yet we immediately recognize it as a completely irrational impulse and chide ourselves for making such a ridiculous feat of illogic. The inanimate object had no intent to harm: and so vengeance is predicated on an illusion.
Yet this is what determinism reduces human behavior to. As people's choices are "animated" by processes set in motion beyond their control, they can be considered "inanimate". And this is indeed the concession we make for many human behaviors. If one is deemed insane, or mentally incompetent, as horrific as their actions may have been, we are forced to remind ourselves that they were operating with mental faculties beyond their control. This is certainly the case with small children. When a two year old hits his playmate in the face with a stick out of anger, we scold him (rehabilitation), but well understand that his behavior was limited by his cognition. Determinism simply extends this conceit to the entire human race, at every level of cognition. Just as the child's consciousness is seen as existing within a framework of cognitive and social development, determinism sees the adult as operating within the same boundaries, just at a higher level of complexity.
For next time...