The hyper-criminalisation of normal human beahviour

By normal human behaviour I'm talking of course about sex and drugs (rock and roll appears to be OK, at least for now). Calls for a 'legal high' (mephedrone) to be banned because it has been linked to the deaths of two lads are complemented by a shadow minister who appears to be saying we should criminalise underage sex to an even greater extent than we do already (or at least punish it more - he's not exactly clear, unsurprisingly).

What is about our current political scene that sees banning, criminalisation and more criminalisation as the only answers to any problem? One answer lies in the very moving interview shown on Channel 4 news with the parents of one of the boys who died. It was awful. But current policy making seems to be largely determined by such emotive moments, rather than a rational debate about the pros and cons of, in this case, making something illegal (class A status has been mentioned, placing mephadrone on a par with heroin and crack). I've yet to see much evidence to suggest that making drugs illegal makes any difference in terms of use or availability (although I stand to be corrected on that).

Don't get me wrong - I think mephadrone is pretty unpleasant drug. I just don't think criminalisation will be some sort of panacea to whatever problems are associated with it - and might even make them worse. This is before taking into account the fact that new 'legal highs' will just spring up to take its place.

Hence the title. It seems to me that taking mind-altering substances are as much a part of the human condition as having sex - and any attempt to over-regulate either is doomed to failure. So let's keep the prison sentences for sexual predators, not teenage fumbles. And let's not automatically ban something because of a few horrible events. At the very least, perhaps there are better ways to deal with the problem.

Update: Another (and interesting) potential reason for over-criminalisation here.