We think that too many people are in jail for too long. But that statement needs to be unpacked. When we say it, we mean each and all of the following:
1. Certain things should not be a crime at all, and shouldn’t be subject to any kind of civil or criminal penalty. Some people shouldn’t be in jail because what they did should instead by legal. For instance, it should be legal to own and sell marijuana.
2. Certain things are wrongful and should face a penalty of sorts, but not a criminal penalty per se. For instance, if you negligently rear-end my car, you should pay damages, but generally speaking, your action should be treated as a tort, as a civil wrong rather than a criminal wrong.
3. Certain behaviors should be subject to some kind of criminal penalty, but imprisonment is not the right way to punish that behavior. In our book, we argue prison should be used only in special circumstances; it should not be the default form of punishment.
4. Certain criminal behaviors should result in someone going to jail, but the person is in jail for too long and under too harsh or bad conditions. One reason why the United States has such a large prison population is that it generally gives out longer sentences for crimes compared to other liberal democratic countries.
What Should Be a Crime?
Here, Chris and I don’t expect we’ll solve the 2,500-year-old philosophical debate about what exactly the purpose of criminal punishment is. Instead, we offer some heuristics:
1. Nothing should be made illegal unless it’s at some point permissible to kill people, or at the very least severely incapacitate them, to stop that kind of thing from happening.
Every act of criminalization is an implicit death threat. It annoys power-loving conservatives and progressives to no end for libertarians and anarchists to say that, but it’s true. As journalistConor Friedersdorf (neither a libertarian nor an anarchist) says:
Law professors and lawyers instinctively shy away from considering the problem of law’s violence. Every law is violent. We try not to think about this, but we should. On the first day of law school, I tell my Contracts students never to argue for invoking the power of law except in a cause for which they are willing to kill. They are suitably astonished, and often annoyed. But I point out that even a breach of contract requires a judicial remedy; and if the breacher will not pay damages, the sheriff will sequester his house and goods; and if he resists the forced sale of his property, the sheriff might have to shoot him.
It is an argument for a degree of humility as we choose which of the many things we may not like to make illegal. Behind every exercise of law stands the sheriff – or the SWAT team – or if necessary the National Guard. Is this an exaggeration? Ask the family of Eric Garner, who died as a result of a decision to crack down on the sale of untaxed cigarettes. That’s the crime for which he was being arrested. Yes, yes, the police were the proximate cause of his death, but the crackdown was a political decree.
Should we threaten to kill people—or ruin their lives—for smoking pot? Eating mushrooms? Snorting cocaine? Doing meth? For selling or exchanging these drugs?
2. The mere fact that something is immoral is not sufficient to make it illegal.
Lots of behaviors are morally wrong, but not all of them or even most of them should be illegal. It’s wrong to cheat on your spouse. It’s wrong to make a false promise to pick your friend up from the airport. It’s wrong to cheat at tennis. It’s wrong not to give some money to an effective charity if you’re rich. If you’re an egalitarian philosopher, it’s wrong not to give most of your money away to others. It’s wrong to grandstand. It’s wrong to waste your own life. It’s wrong to wear a Che Guevera T-Shirt or carry a Nazi flag. Nevertheless, while all these behaviors are morally wrong, it does not follow that they ought to be criminalized or punished.
3. Criminalization has to work
Imagine an evil demon announced that if we criminalize, police, and prosecute murder, it will use its dark magic to ensure that even more murders take place. For every criminal we charge with murder, it will make two more murderers appear.
This wouldn’t change the moral status of murder. It would still be wrong. But it would change what we should do about murder. In this case, we should not use criminal law to try to stop murders…precisely because murder is so bad.
This is a silly hypothetical, but real-life analogs exist. The drug war is a perfect example. Criminalizing drugs not only fails to reduce drug use, but in fact generally increases it, increases the strength of the drugs on the market, increases the profits to be made from selling drugs, decreases the safety of the drugs, and leads to criminal violence as drug sellers try to police their territories and enforce private contracts. In this case, we should not use criminal law to try to stop drug use…precisely because drug use is so bad.
4. Criminalization has to be worth the price we pay.
Imagine a different evil demon announces that it will use its dark magic to ensure that prosecuting a murder would cost us $1 trillion per case. Again, this would not change the moral status of murder, but it would change what we should do about it.
If something is a matter of justice, then it feels callous or monstrous ask whether we can afford it. How can you put a price on justice?
The economist and philosopher David Schmidtz responds, “Some things are priceless. So what?” We might decide that dolphins are the world’s priceless heritage. But if it costs $2 billion to save one priceless dolphin, that’s still $2 billion we’re not spending saving all the other priceless things out there.
Again, the silly demon thought experiment has real-life analogs: Take the drug war again. The United Nations estimates that three quarters of imported drugs would need to be seized before the profitability of the illicit drug trade is significantly compromised. At current levels of police power, only 13 percent of heroin and on average 25 percent of other drugs are confiscated. This means that effectively enforcing the law—enforcing it to a level that would actually significantly reduce drug use—is prohibitively expensive.
Before criminalizing something, you need to ask, how much will it cost and is it worth that cost? That also means asking, of all the ways to enforce and punish that behavior, which way gets us the most bang for the buck?
5. Will the government be competent to police the action?
Someone should be given (significant) power only if they will use that power competently and in good faith. We take this to be a theory-neutral minimal condition of the right to exert power over others. Power: use it well or lose it.
When we decide how much power to give people, we shouldn’t imagine them to be omniscient angels who always and only do the right thing. Instead, what government is allowed to do depends on how well they’ll actually do it. There are things we might want a government of angels to accomplish but which we shouldn’t dare let a government of real people even attempt.
6. Can something be handled as a tort instead?
Instead of criminalizing something, can it be handled through a tort system? Might we instead make it easier for people to sue each other for certain kinds of harms—perhaps even by using money now spent on criminal justice toward this end—and then require wrongdoers to compensate their victims?
Note that we can still use exemplary damages to ensure the rich don’t see this as a license to harm anyone they like. (Paying $10,000 to punch someone in the face might seem like a good deal to some.)
We might also use fines, fees, and the like to pay into victim restitution funds.
We haven’t given you a full theory of criminal law here. However, we think these heuristics tell us the scope of criminal should be narrowed. We can debate just how much.
 Brennan, Jason, “Marijuana,” in Ciment, James, ed.,Social Issues in America (Armonk, NY: M.E. Sharpe, 2006), 1044–54.