The higher question is why shouldn't society be punitive?

To start with prison/justice, rape/violence being a feature means gang support systems are a feature, and crime university is a feature. Police are empowered by being agents of punishment. Privatization of parts of justice system incentivize kickbacks for punishment, and school to prison pipeline for the structurally oppressed classes.

Structural oppression in society serves oligarchist low hanging fruit of wage suppression. Structural desperation that motivates gang/mafia membership and crime as alternate protection from a punitive society. Importantly, if society isn't hateful, corrupt, and punitive, then why the fuck would you care about a politician who champions putting bandaids on it to make society more hateful and divisive, even if their real agenda is more war and service to Israel? Late stage democracy ensures collapse for zionist oligarchist pillaging.

UBI/freedom dividends is the only democratic idealist function. Not political power. It eliminates structural crime and oppression. Liquid democracy with UBI eliminates corruption and dysfunctional policy. A functional improving sustainable society is impossible when hate is prioritized.

The question doesn't really make sense as asked. The entire criminal justice system, almost by definition, revolves around punishment.

Punishment has several different purposes such as deterrence, removal, rehabilitation. I suspect you wanted to ask about why some of these purposes are "better" than others…

Here's a comic explaining this: https://lawcomic.net/guide/?p=60

Punishment is part of justice. Seeing that somebody who does wrong intentionally and with malice suffers, proportionally, is part of the lesson that the justice system teaches.

In my opinion, punishment is important for the victim (to see that they are protected, and to satiate any craving for extra judicial revenge), society at large (to demonstrate that there is a governing body that will not let people get away with causing harm), and for the criminal themselves (to show that harmful acts will result in reprisal).

It crucially can't be the whole lesson, though. There has to be guidance, forgiveness (on a legal level), and a corrective path available to people who hurt others. Punishment on its own often just perpetuates systems that produce criminality, and isn't enough to effectively reform people who have done wrong.

It doesn't prevent crime

Because rehabilitation is more effective

Punitive justice won't change the way people think, the cycle will just repeat

Things like the death sentence don't work, because people are still murdering, even though they know that they face execution for it

It's a pointless punishment

rehabilitation is better

however, we do have to do something with those billionaires and oligarchs

Well, it isn't that punitive measures serve no purpose. They do. But that purpose doesn't decrease the chances of a given crime occurring by other people, nor does it prevent the same people repeating a crime. To the contrary, the way most prisons work, chances are that anyone going on comes out with less options, and more knowledge of crime, so even if they don't repeat the same offenses, they're put in position to do others out of necessity.

But it does seem to make people feel better when someone else gets punished for doing something wrong. Which, in theory, is going to reduce vigilantism and mob justice. In practice? I dunno, I haven't seen enough data to form an opinion about that specific matter.

Generally, the reason it shouldn't be the main goal of a justice system is lack of efficacy. It just doesn't do what people want it to do. So, what's the point of that?

If your goal is to reduce crime, and reduce recidivism, rehabilitation has shown to do a better job. Prisons should be the last resort for non violent crimes, not the first. Even then if prisons hope to do more than isolate repeat offenders, they would need to have more intensive measures to help people change.

For me, personal justice almost has to be punitive. But I'm an asshole. And more importantly, I'm not society, just an insubstantial slice of it. Any study on how to deal with crime shows that punitive measures rarely, if ever, increase the wellness of society. Rehabilitation, understanding, hippie dippy shit, has a much greater positive impact on society, as hard as that may be to stomach. Facts are facts, regardless of feelings.

The world has had punitive justice systems for hundreds of years. It doesn't work. The countries trying restorative and rehabilitative justice systems are seeing amazing results.

Before we can answer that question usefully, tell us what you think justice is, and what purpose it serves.

It could be; but, the ones advocating for the punitive punishments rarely consider that their own heads could be next on the chopping block (sometimes literally).

There's also a bunch of research that seems to say that rehabilitation is typically better at preventing crime.

It shouldn't be, period. As long as we keep producing people having no problem with causing more harm than good, they will keep doing just that

I don't think criminal law can be useful without punishment.

In criminal law, a sentence forms the final explicit act of a judge-ruled process, and also the symbolic principal act connected to his function. In criminal law, a sentence is the punishment for a crime ordered by a trial court

I did find https://en.wikipedia.org/wiki/Criminal_law#Objectives_of_criminal_law interesting.