Bryan Caplan has been carrying on an interesting discussion of gender equality, liberty and marriage law with Jason Kuznicki. That post makes a handful of points about the libertarian response to things like coverture (a legal arrangement of marriage in which a woman surrenders some autonomy in legal matters). Without getting into all the points that he's making, he does say the following about what the response to what bad laws should be:
3. Degree of enforcement. Suppose the government has one unalterable definition of marriage, and officially bans all other arrangements resembling marriage. If it strictly enforces its laws, then this is very coercive indeed. The less it's enforced, the less coercive it becomes. At the other extreme, if the laws against other arrangements are never enforced, then it's hard to see the big deal. Virginia still officially bans cohabitation. But since the law is a dead letter, it's no more than mildly coercive.
Here I have a small quibble. There is a harmful effect of unenforced/unenforceable laws that's not mentioned here. Maybe it doesn't rise to the level of a "big deal," but it's still there. Unenforced laws restrict freedom unequally. They only affect the behavior of the conscientiously law abiding. Consider 1 Peter 2:13:
Therefore submit yourselves to every ordinance of man for the Lord’s sake, whether to the king as supreme, (NKJV)It doesn't say to obey only laws believed to be just. Now those who actively, if imperfectly, try to live out this principle may be in a small minority (and may do so for any number of reasons not limited to living Biblically), but it does mean that some of us alter our behavior against our 'druthers based on laws that we find unwise for any number of reasons, whether practical or principled or both. One can imagine a law that outlawed, for instance, ice cream consumption as being very anti-liberty. However, if the law is not enforced at all, there are still those who feel compelled to obey it and limit an otherwise innocent pleasure.
Taking it just a bit further, I also have to wonder if having a legal code filled with well-known, but wholly ignored laws, would engender in society a blase attitude towards following the law. "If I think it's right and I don't get caught, what's the harm?"