There are at least three different kinds of justification generally given for intentionally punishing those who have done something wrong. One is partly utilitarian in nature and it is the grounds usually discussed in the media when issues such as the justification of capital punishment are raised. Yet it is less relevant to capital punishment than the other two.
Of course, these justifications are about punishing the guilty, not about mistakenly punishing the innocent, even if they are thought to be guilty and even if, in a court of law, they are mistakenly convicted of a crime they did not actually commit. It also presupposes that the act for which one is being punished actually is something that is wrong to do, and is not something that is merely unreasonably illegal or mistakenly unjustifiably and unreasonably regarded as wrong.
1) Punishment as a deterrent of future wrong-doing, where it works to deter either the same person's repeating the offense (or intentionally doing other wrong things) or where it serves to deter others from committing the same (or other) offense. Punishment sometimes is a deterrent, and as long as it is not a draconian or unfairly harsh deterrent, or is not otherwise inappropriate for the crime or misbehavior, particularly when less harsh or more appropriate deterrents are reasonably available, and as long as the conditions above are met -- that the person actually is guilty and the act for which they are being punished actually is wrong -- and as long as there are no mitigating circumstances and where mercy is not justified, it may be employed. In other words, if there are two possible punishments that are both appropriate on other grounds, the one that will also serve as a deterrent is better than the one that won't. Where punishment does not serve as a deterrent, this attempt at justifying it does not apply and cannot be grounds for administering punishment. It is an empirical question whether punishment in a given instance acts to deter crime or not. Yet it seems that a person who has done something seriously wrong should still be punished, even if it "does no good" for deterring his or anyone else's future bad behavior.
There are two different ways in which punishment may serve as
a deterrent when it does. Some punishments act as a deterrent by
making someone fear the
consequences of (being caught) committing an act, but there are
punishments meant more to impress upon perpetrators the seriousness of
their act than to behavioristically scare them into not doing it
again. A loved
one's showing profound disappointment or anger may do more to get a
person to see that what he did was seriously wrong and ought not to be
repeated than it will to make him simply eschew repeating the act out
of fear of an unpleasant response. Similarly with a strong
condemnation by a judge prior to sentencing a convicted person, or as
his rationale for the sentence being handing down. One can
consider these things to be part of the punishment or as something
separate from the punishment. In some cases, they will be
intended for one purpose more than another, the difference being
whether the punishment is meant to make the person suffer or to get the
person to take seriously his crime or misbehavior and truly understand
that what s/he did was wrong. When punishment is intended to
"teach you a lesson," the lesson may be either or both that the
behavior was wrong (and thus is something no person who truly wants to
be good will do) or that it will not be tolerated without unpleasant
consequences for the perpetrator whether s/he cares about what is right
or wrong, good or bad, or not.
2) Punishment as being earned and deserved as a fitting consequence to doing evil. In this case, punishment has the same sort of justification as a reward or as thanks and appreciation. It is something that is deserved, based on the actions of the person who has done the deed. It is not "forward-looking" as are utilitarian considerations, trying to find out what will do the most good in the future, but it is "backward looking" in the sense of trying to find out who has done good, or harm, in the past, and acting in some way to fittingly treat those who have done either.
Suppose, in a simple case, someone steals money from another. Surely s/he should at least have to pay back the money. But I believe s/he should also have to pay for the aggravation and grief s/he has caused as well. Perhaps s/he should have to pay for the efforts of the police to apprehend him/her, perhaps the cost of any incarceration if incarceration is necessary.
In a crime where what is taken cannot be repaid - murder,
irreplaceable property loss, defamation of character, etc. - it seems
something else must be paid besides money, whether it is by the labor
the guilty party or by some other means to try to make up in some way
what was lost.
Yet something seems wrong in both cases, for we would not let
someone pay first to commit a terrible act, such as murder or
rape. And I doubt we would say it is okay for someone to steal
our car and lead police on a wild chase, etc. if he paid the costs of
doing so ahead of time. So the notion of paying for a crime or
wrongdoing does not seem to fit; it is not like paying for a candy bar
that one then has the right to take and eat or paying inside the store
for $30 worth of gas one then has the right to pump into one's tank.
If we were to act only on utilitarian -- merely forward-looking-- grounds, we would be compelled to reward or bribe people before they have done good things, and punish people before they have done bad things; but once they have done either good or evil, nothing should be done about it because it is "too late" to affect their past action. We would only be trying (perhaps unnecessarily) to reinforce their good acts or (perhaps unsuccessfully) to change their bad behaviors. In fact, one of the utilitarian arguments against capital punishment is that it won't bring back the victim and it often is not a deterrent to others. But no punishment will bring back a murder victim or restore the former peace of mind of a rape or torture victim, and also it seems odd, at least, to be willing to harm someone to prevent future crime but not harm them for having committed a past crime. A possible future crime or intention or threat to commit a crime is surely not as bad as having already done it, so why should we be willing to inflict a harm in the form of a deterrent that we would not be willing to inflict in the form of a punishment. It is like saying to someone who is about to break an expensive item in your store that it will cost him at least $25,000 if he does that, and then after he has done it, saying since it is broken, it is not worth anything any more but you want $50 to pay for the clean up of the mess he caused. Or it is like saying that it will still cost him $25,000, but not for the one he broke, since it is already broken, but for one he has not broken but might.
Further, on utilitarian, forward-looking, grounds, good people should receive no incentive or attention because they are likely to do good, but people who are about to do great harm should be either coerced or paid not to do it. Incorrigibly good people can be ignored because they need no external incentives to do the right thing.
3) The strongest argument, I believe, is an extension of
the view that...........