Why Do We Punish? And Who Gets to Do It?

Imagine your little brother takes your phone without asking and drops it, cracking the screen. Your parents find out. He says he’s sorry, but you’re still furious. What should happen next? Should he have to pay for the repair from his allowance? Should he lose his own phone for a week? Should he have to write you an apology letter? Or should the whole thing just be dropped?

Now imagine a stranger snatches your mom’s purse on the street. That’s different, right? It’s not just between you and the thief anymore. The police get involved. There’s a trial. If the thief is caught and convicted, they might go to jail.

Why are these two situations handled so differently? When your brother damages your phone, that’s a family problem. When someone steals a purse, that’s a crime. But what makes something a crime in the first place? And why does the government—not just the victim—get to decide what happens to the criminal?

These are the kinds of questions that philosophers of criminal law try to answer. And as you’re about to see, they don’t all agree.

What Makes Something a Crime?

Here’s a surprising fact: making something a crime isn’t just about saying “don’t do this.” When a law says “murder is a crime,” it does a whole bunch of things at once.

First, it says that murder is wrong—the law doesn’t want you to do it even if you’re willing to accept the punishment. Second, it gives police the power to stop you before you murder someone, using force if necessary. Third, if you do murder someone, it gives the police power to arrest you, search for evidence, and hold you for trial. Fourth, it creates a whole process—arrest, charge, trial, conviction, punishment—that’s controlled by the government, not by the victim or the victim’s family.

This last point is really important. If someone hurts you, you can’t just go and hurt them back. That would be “vigilantism,” and it’s itself a crime. Only the state gets to punish. For crime victims who want revenge, this can be incredibly frustrating—especially if the state doesn’t do anything, or does something too light. But philosophers have reasons for why this system exists, even if it’s imperfect.

Think about it this way: in most countries, if someone hits you, you can sue them for money. That’s a civil case, and you (the victim) control it. You can decide not to sue. You can settle out of court. But if someone hits you in a way that’s a crime, you don’t get to decide whether they’re prosecuted. The state decides. Even if you desperately want the case dropped, the state can keep going. And even if you desperately want the case pursued, the state can drop it.

That’s a weird amount of power to give to the government, isn’t it? Especially since criminal punishment can be incredibly harsh—prison, fines, a criminal record that makes it hard to get a job or housing or even travel to other countries. So philosophers want to know: is this system justified? What’s it for?

What’s the Point of Criminal Law?

Philosophers have proposed several different answers to this question. Here are the main ones.

The Punitive View. Some say the whole point of criminal law is to deliver justified punishment. A criminal commits a wrong; they deserve to suffer for it; the criminal law exists to make that happen. On this view, everything else—the rules about evidence, the trial process, the protections for the accused—exists to make sure we only punish the right people, and that we don’t punish them unfairly.

The Curial View. Others say the criminal trial itself is the most important thing. When someone commits a serious wrong, they owe an explanation. They should have to answer for what they did. The trial is where that happens. The defendant is called to account—they can deny it, or confess, or offer a defense. Even if they’re not punished in the end, the process of calling them to account has value. Imagine someone kills in self-defense. On the punitive view, since they don’t deserve punishment, the criminal law has failed. On the curial view, the trial still served a purpose: the killer explained themselves, and the community heard that explanation and judged it acceptable.

The Preventive View. Some say the main point of criminal law is to prevent crime from happening in the first place. Ideally, nobody would ever commit a crime. Punishment is a backup plan—something we resort to when prevention fails. If you think about it, a world where every criminal gets caught and punished isn’t really a success for the criminal law. A world where nobody wants to commit crimes because the law has made it clear they’re wrong—that would be success.

Mixed Views. Most philosophers think the truth is a combination of these. The primary goal is prevention: we want people not to commit crimes. Failing that, we want them called to account. Failing that, we want them punished. Different parts of the criminal justice system serve different purposes at different stages.

But What Justifies All This Harm?

Even if we agree on what criminal law is for, there’s a deeper question: what gives anyone the right to do all this? To arrest people, hold them in cages, make them suffer? The criminal law causes a lot of harm, even when it works perfectly. So why is it okay?

Here things get really philosophical. Different thinkers give different answers.

Some, following the philosopher Immanuel Kant (who lived in the 1700s), say that criminal law helps create a certain kind of relationship between people. Without law, we’re all dependent on each other’s goodwill—like slaves depending on their masters. We need to know our rights will be respected, and that if they’re violated, something will be done. Criminal law gives us assurance and reasserts the importance of rights when they’re violated. Its value is that it helps us live as independent beings, not as masters and slaves.

Others say criminal law’s value comes from the fact that we live in a political community. Communities have values—like respect for life, or property, or personal safety. When someone violates those values, the community has to respond. Otherwise, the values are just words on paper. The criminal trial and punishment are how the community says “no, this matters to us.” On this view, the criminal law helps the community stay true to itself.

Still others say the justification is simpler: criminal law prevents harm and responds to moral wrongdoing. People get hurt when crimes happen. Criminal law reduces that hurt. That’s enough to justify it. This view faces some objections, though. For one thing, not all moral wrongdoing is the criminal law’s business. If you’re lazy and don’t help your friend move house, that’s wrong, but it shouldn’t be a crime. For another thing, some things that aren’t morally wrong might still need to be crimes—like driving on the left side of the road in countries where that’s the rule. (It’s not morally wrong to drive on the right; it’s just illegal. But we need everyone to do the same thing for safety.)

What Should Be a Crime?

This is where the rubber meets the road. Everyone agrees some things shouldn’t be crimes—like having unusual but harmless hobbies, or holding unpopular political beliefs. But how do we draw the line?

One famous answer is the harm principle: it should only be a crime to harm others, or to unreasonably risk harming them. This sounds simple, but it gets complicated fast. What counts as “harm”? Does emotional distress count? What about harming yourself? What about consensual harm (like extreme sports where people might get hurt)? Should we criminalize things that don’t harm anyone but that most people find deeply offensive?

Another famous answer is that only morally wrongful conduct should be criminalized. This also sounds reasonable, but it has problems too. Remember the driving example? Driving on the wrong side of the road isn’t morally wrong in itself—it’s wrong because it’s against the law. So on this view, a lot of traffic laws would be unjustified. Maybe that’s okay—maybe traffic violations should be handled differently than “real” crimes. But many philosophers think that’s too radical.

Still other philosophers think there’s no simple rule at all. They say we just have to look at each proposed crime and ask: does the good it does outweigh the harm it causes? Will it actually prevent wrongdoing? Will it be enforced fairly? Will it make things better or worse? The answer will be messy, they say, but that’s what reality demands.

This debate isn’t just academic. Think about laws against drug use. Some countries criminalize it, trying to prevent harm. Others have decriminalized or legalized it, arguing that criminalization causes more harm than it prevents—through violent black markets, ruined lives of people with criminal records, and the difficulty of getting help if you’re afraid of being arrested. Both sides are making philosophical arguments about the limits of criminal law.

When Are You Responsible for a Crime?

Let’s say we agree that something should be a crime. Now the question is: who should be held responsible for committing it?

Most philosophers agree that you should only be criminally responsible if you had some kind of bad intention or awareness—what lawyers call mens rea (Latin for “guilty mind”). If you accidentally break someone’s window because a gust of wind blew you into it, that’s not a crime. If you throw a rock at a window on purpose, that’s vandalism.

But not everyone agrees on how much awareness is required. Should you be responsible if you should have known you were creating a risk, even if you didn’t actually realize it? That’s called negligence. Some philosophers say no—that real culpability requires awareness. Others say sometimes our ignorance itself is blameworthy, like if we don’t notice risks because we’re arrogant or indifferent.

There’s also disagreement about how much your actions have to cause the bad outcome. Imagine you shoot at someone intending to kill them, but you miss. You’ve attempted murder. Now imagine you shoot and actually kill them. Should you be punished the same in both cases? After all, your intentions were the same. The only difference was luck—the bullet happened to hit, or miss. Some philosophers argue that criminal responsibility shouldn’t depend on luck. Others say it matters a great deal. In most actual legal systems, the attempted murderer gets a lighter sentence, even though their intentions were just as bad. Is that fair?

Why Governments Get to Punish (And You Don’t)

Remember the beginning of this article? Why can’t victims punish criminals themselves? Why does the state have to do it?

One answer is that the values that justify criminal law—like securing our independence, or expressing the community’s judgment—can only be realized by the state. Only the government can speak for all of us. If a private person punishes someone, they’re just one individual imposing their will. That doesn’t create independence; it just replaces one form of domination with another.

Other philosophers disagree. They say the values that justify punishment—like preventing harm or holding wrongdoers accountable—could in principle be realized by anyone. The reason we don’t let private individuals punish is practical: they’d make more mistakes, they’d be more biased, they’d be harder to control, and they’d be more likely to settle scores than to do justice. The state is (ideally) more careful, more consistent, and more accountable. This is a reason to give the state a monopoly on punishment, but it doesn’t mean private punishment would be impossible—just that it would be a bad idea.

This debate has real-world implications. Think about private prisons or private security companies. If criminal justice requires state action to be legitimate, then privatizing parts of it might be wrong in principle, not just in practice. Or think about arguments for “restorative justice” programs where victims and offenders meet to work things out outside the formal court system. Are these valuable alternatives, or do they undermine what makes criminal justice special?

Still an Open Question

After all this, you might be frustrated that there are so few definitive answers. But that’s partly what philosophy is—exploring the reasons for and against different positions, without pretending things are simpler than they are. Most philosophers of criminal law think the system we have is deeply flawed—it punishes too harshly, it’s applied unfairly to different groups, it doesn’t always prevent what it should. But they also think some form of criminal law is probably necessary.

The question is: what form? Until we understand what criminal law is for, and what justifies it, we can’t really say how it should work. And those questions are still very much alive.

Appendices

Key Terms

Term	What it does in this debate
Mens rea	The “guilty mind” element of a crime; the idea that you should only be responsible if you had some awareness or intention regarding what you were doing
Harm principle	A proposed limit on criminalization: only conduct that harms others (or risks harming them) should be crimes
Vigilantism	Private individuals punishing others for crimes; the criminal law forbids this, reserving punishment for the state
Punitive view	The claim that criminal law’s main function is to deliver justified punishment to wrongdoers
Curial view	The claim that criminal law’s main function is to call wrongdoers to account in a trial, not just to punish them
Justification	A defense that says what the defendant did was actually the right thing to do under the circumstances (like self-defense)
Excuse	A defense that says the defendant did something wrong but shouldn’t be blamed for it (like acting under extreme duress)

Key People

Immanuel Kant (1724–1804) — A German philosopher who argued that criminal law helps secure our independence from each other, transforming us from dependents into free beings.
John Stuart Mill (1806–1873) — An English philosopher who famously argued that the only justification for interfering with someone’s freedom is to prevent harm to others—a key source of the harm principle.

Things to Think About

If you could design a completely new criminal justice system from scratch, what would it look like? Would you keep trials, prisons, and police, or replace them with something else? What values would guide your design?
Imagine a machine that could perfectly identify guilty people and administer the exact punishment they deserve, with zero chance of error. Would it be okay to use this machine instead of having trials? What, if anything, would be lost?
Some people argue that certain “victimless crimes”—like using drugs in private, or gambling, or selling your own organs—shouldn’t be crimes at all. Others say they should be, because they harm the people who do them, or because they harm society as a whole. What do you think, and why?
Should corporations be punished for crimes? They can’t go to jail, and they can’t feel shame. Should they just be fined? Or is there something wrong with the whole idea of “corporate crime”?

Where This Shows Up

In the news: Debates about drug legalization, policing reform, and prison abolition all involve philosophical questions about what should be a crime and who should enforce the law.
In school: When you get detention for something, was that punishment, or was it about calling you to account? Do the rules seem fair? Who gets to decide? These are mini versions of the same questions philosophers ask about criminal law.
In video games and movies: Stories about vigilantes (like Batman or the Punisher) are basically thought experiments about whether private punishment could ever be justified.
In everyday life: When someone wrongs you and you have to decide whether to “make them pay,” report them, or let it go, you’re grappling with the same tensions between punishment, accountability, forgiveness, and prevention that criminal law deals with at a society-wide scale.