I always enjoy watching public figures crash and burn, and this has been a great year for it: Eliot Spitzer, Larry Craig, Michael Vick. But in my mind, I don’t think any of these people did anything wrong. These men are only guilty of breaking arbitrary societal taboos.

What moral principle does hiring a prostitute break? If it is illegal to hire someone to have sex with you, then why is it legal to pay two people to have sex and film it? And if it is considered cruel to make animals fight for your amusement, why is it legal to force them to race each other, or to force-feed them in tiny cages just to satisfy the public’s insatiable desire for buffalo wings?

Every society has taboos — Hindu culture forbids menstruating women from entering a Hindu temple. The difference is that in America we feel this need to justify our social taboos rationally. We try to tell people that these laws are for their own benefit. But they’re not. I’m sure people would be much happier if they were allowed to do what they wanted. Personally, I think I’d enjoy a good dog fight. There are all kinds of countries where watching animals kill each other is perfectly legal and no harm has come to their people. For instance, the forty thousand people I saw at a bull-fight in Barcelona didn’t seem to be a terribly cruel set.

I think we make these arbitrary restrictions, however, so that we know who we can trust. By banning things people enjoy, we can test how much someone cares about societal approval. People who are unable to restrain their impulses, even when they know what they are doing is considered “wrong,” should not be allowed to enjoy positions of power over other people.

If someone is willing to break the law in order to gain some momentary pleasure, it tells us that he doesn’t really care about those around him or the integrity of civil society. It does not matter whether the law makes sense. What matters is that society has decreed that certain things are not to be done. And if someone is willing to ignore what other people tell him to do, it indicates that he places his own well-being above that of those around him. And everyone else should be wary of placing trust in someone who cares more about his own self-interest than in obeying the law. This distrust can be extremely valuable information in situations where a breach might not be nearly so visible, like business deals or government administration.

Seen in this light, many laws make perfect sense, especially those dealing with drug use, which often limit a behavior that is not directly harmful to other people and is generally enjoyable. In the same way that a Catholic might show his obedience to God by not eating meat on Fridays, we require that everyone in America show his obedience to public opinion by not smoking marijuana.

The consequences of breaking one of these taboos are not particularly dire, legally speaking. I doubt Eliot Spitzer or Larry Craig are going to become part of the prison population. But the social consequences, such as having to resign from the governorship, are completely justified. At some level, obeying the law becomes its own morality. And a failure to obey becomes a sin in and of itself.

Contact Rahul at rahkan "at" stanford.edu.