It is a great temptation for people in government to mete out harsh punishment after something happens which they do not agree with or support. Whenever some incident bursts onto the public consciousness and raises an outcry, government officials almost always feel the urge to use their power to explicitly punish whoever is responsible. The BP oil spill is just the most recent (and most glaring) example of this right now. But there's one problem with national politicians elbowing each other out of the way to punish individuals or companies in such a fashion -- it's not only illegal, it's downright unconstitutional to do so.

Here is the relevant text:

No Bill of Attainder or ex post facto Law shall be passed.
-United States Constitution, Article 1, Section 9

In two ways, this prohibits Congress from ever passing a law whose sole purpose is to punish someone or some company. The first part specifies that Congress cannot single any person or company out, ever, for any law (a "Bill of Attainder"). Congress, at times, ignores this and tries to do exactly what the Constitution forbids -- make laws specifically for (or against) one individual or one specific group (see: Terri Schiavo, ACORN). But the second clause is even more specific. The Latin phrase ex post facto is just a fancy way of saying "after the fact." What it means is that any action by anyone (person or company) cannot be made illegal (or punished more severely) after it happens. In other words, any event must be judged by the laws that are on the books when the event takes place. You cannot go back and make something illegal after the fact, even if it makes you feel better to do so.

Which is precisely the point. It's human nature to want to punish severely when the circumstances demand such punishment. But you cannot impose such punishments looking backwards, because forwards is the only way the law can change. Otherwise, you'd never know if what you did quite legally today would be made illegal tomorrow, retroactively. It would quickly lead to legal (and societal) chaos.

The only constitutional way to scratch the itch of punishing something after it has happened is to strengthen the law for the next time the action takes place. Which is usually worthwhile, provided legislators don't go overboard in the nature of the punishments they're creating.

BP made (and is still making) a mess in the Gulf of Mexico. Everyone's angry about that, and angry with BP. Fine and good. But in the rush to "make them pay" we all (politicians included) need to take a deep breath and realize that the only remedy possible is to strengthen such laws as is necessary -- for the next time. Current liability caps on damages are inadequate, obviously. Perhaps the whole idea of "liability caps" needs throwing out. Perhaps stronger safety regulations need passing. Perhaps "fail-safe" devices should have to undergo rigorous testing (in 5,000 feet of water) to prove that they will work as designed, before a disaster happens.

There are many ways legislators can change our laws, to ensure that we reduce the risk of this ever happening again to as close to zero as possible -- and to ensure that if it does happen again, we are a lot more prepared to deal with it (both technically and legally). There are many ways to achieve this, and they all should be explored.

Legislators should also realize, in the specific case of oil spills, that "worst-case scenarios" are not just some dark fantasy dreamed up by environmental extremists. Sometimes the worst case actually happens, as BP has demonstrated beyond a shadow of a doubt. Legislating preparations -- before the fact -- for such worst-case scenarios is a worthy goal which should now get a lot of attention on Capitol Hill.

But in many of the stories so far, both the media and (sadly) some members of Congress don't seem to understand one very basic fact of constitutional law. You cannot fix things legislatively after they happen. The framers of the Constitution forbid it for a very good reason. And, even though the urge to do so becomes overwhelming at times, it doesn't change one word of the ex post facto clause in the Constitution.

So, in the discussion of "what to do" about the BP oil spill (which will continue long after the well is finally capped), both in Washington and across the country, we would all do well to remember this simple concept. You can make laws before something happens to mete out punishments, but you cannot do so after the fact. I'm not overly fond of BP right now, and I'm certainly not trying to be any sort of BP apologist, but I seem to be one of the few who realizes that no matter what happens to them in the way of punishment, it will happen under the laws which were in place when the accident occurred. It is simply impossible to change any of that now, because the Constitution expressly forbids it. For good reason.

-- Chris Weigant

Follow Chris on Twitter: @ChrisWeigant