Via Instapundit and the NRO, I find Mr. Yglesias defending liberal anti-discrimination laws against libertarians who would oppose them (at Cato Unbound):

Certainly Barry Goldwater, probably the most libertarian major party presidential nominee we’re likely to see, didn’t think much of a giant pile of regulations telling people what they can and can’t do with their own property called the Civil Rights Act.

Nor has the feminist movement’s success in transforming traditional attitudes about sex and the role of women been innocent of un-libertarian deployment of state power. Discriminating against women in the workplace has become not just inefficient or impolite but actually illegal thanks to a series of heavy-handed regulatory initiatives that no libertarian could in good conscience endorse.

Similarly, the gay rights movement does indeed want gay couples to be unmolested in their private conduct. But their demands go far beyond that. They want to regulate who you may employ, who you may rent a house to, etc., etc., etc. — not merely a state that refrains from discriminating, but a state that takes the lead in fighting discrimination.

But my question is: how effective is that fighting?

Basically the argument goes: it’s okay to pass social engineering laws, so long as they’re ones with good goals. And I can’t help but agree that the goals are indeed good. In my opinion, the error he makes is in ignoring the question of effectiveness: did those laws actually cause those agreeable results, or were they fellow symptoms of a generally progressifying society? I don’t think there’s anyway to collect data about this (Sir, did you stop hating minorities and women because of the law, or because the people around you became less tolerant of it?) and even less ways to disentangle the many reasons of why we now exist in a relatively more tolerant country.

So my only option is to compare the methods of these “noble” (and ostensibly successful!) social engineering plans with other, less successful ones: what did they do wrong that the Civil Rights Act did right? Let’s choose perhaps the largest social engineering plan ever: the Drug War. This provides us with an excellent comparison: even if Mr. Yglesias believes that legal means were the primary cause of the liberalization of society, he must admit that a parallel shift in opinion was taking place. With the Drug War, we have a shift in opinion that is opposite to the social engineering law: people deciding that drugs are not as bad as they used to be. So, when general opinion and law come in conflict, who wins? It should be pretty obvious that the social engineering faction isn’t winning the drug war.

This course of failure has largely defined the success of conservative social engineering — laws Mr. Yglesias would no doubt join me in condemning — liberalizing public opinion makes them laughably impossible to enforce. Strangely, both methods of social engineering used the exact same tool: simply outlaw the undesired activity. Yet the goals of the anti-discrimination laws have largely been achieved — while Prohibition and the Drug War have been monstrous failures. The difference is public opinion. When social engineering laws are a “success” it is because they act in concert with already-underway shifts in public opinion.

I think the flaw is in thinking that the only thing you must do to achieve something is pass a law mandating it.

Now, I don’t wish to imply that such laws have zero impact: of course the sexist CEO will consider the fact that he may be arrested for his actions before committing them, but I feel that other factors most likely overrode them. To return to the Drug War comparison, we have seen so many stark examples of how the impact of peers, family and institutions (and flat-out short term self-gratification) can completely overwhelm the influence of the law.  If society were truly bent on retaining its racist and sexist viewpoints, I don’t believe any law could stop them, just as those same type of laws have failed so completely to stop drug usage.

Now, unlike the Civil Rights Act, the Drug War seems to have quite a few negative side effects. So the question becomes: do the benefits outweigh the costs? Here Mr. Yglesias can take some hope: when you pass laws in concordance with public opinion (even if libertarians think you shouldn’t) the negative side effects are greatly reduced because the worst part of any social engineering law is the cost of keeping the rebellious in line. So the Civil Rights Act had few negative outcomes because so few (relatively speaking) people had to be prosecuted for violating them. Don’t think so? How many people have ever been punished under any anti-discrimination law as compared to drug laws?

Unfortunately, (and here’s my slippery-slope argument) there is one last secondary negative side effect: precedent. If you establish that it is legal to use the law to mold individual behavior, then surely there will be bad outcomes down the road, even if we start off only punishing bad things. We only think about using the law to stop truly bad things, because we’re all nice people — but politicians can think of lots of other bad things that people do, like criticizing them, voting for their opponents or not giving them enough money. When we grant the state power to do this, then they will use and abuse it, because they do not see things in terms of good social engineering or bad (they think they do) but rather in terms of power. And social engineering laws provide the best kind of power, often with disturbing consequences unintended by their crafters.

So, in the end, I’m willing to grant that some anti-discrimination laws, due to their concordance with evolving public opinion, have very few bad side effects (outside establishing the precedent for massive social engineering) that are outweighed by the effect on said undesirable actions. So that’s the reason I’m happy with the Civil Rights Act and so many of the other examples. Yes, I suppose I would theoretically be opposed to a law that said you must always continue to breathe, but my actual opposition to it would be pretty limited. I just think it is a mistake to credit the massive sea shift in public opinion and action that took place to these laws — and, by extension, to imply that opposition to those laws necessarily means opposition to their goals.