So, once again Sir Ian Blair, Metropolitan police commissioner, is targeting the Hampstead dinner party set and its use of cocaine. Apparently he's going to have "smartly dressed" officers posing as dealers in the sort of bars and clubs where posh people get their coke. He wants to stop it replacing wine at smart middle class dinner parties.

Now, fair's fair, his officers have long made life hell for poor users of cocaine and its sister freebase-cocaine, or "crack", so it's probably about time this law officer enforced the law more equally for all. But the lines he's using (sorry! I couldn't resist that) are that middle class coke use is not a victimless crime, that people in north London estates die to perpetuate the supply of coke and that the cocaine plantations of Columbia are now the land mine capital of the world.

So, do we finally have the appalling admission that the law itself, rather than cocaine use, is causing this killing? Why doesn't he do something about that, speak out on that? After all, he has shown himself and his organisation very capable and willing in the past not merely of enforcing existing laws, but in lobbying for changes in the law relating to terrorist activities that threaten all our civil liberties.

Cocaine has been used in a variety of forms, safely for the most part, for thousands of years. The peoples of its native growing area, the Andean mountains of South America, have chewed leaves as a pick me up since they arrived there. It helps them to cope with high altitude living by increasing circulation and therefore take-up of oxygen. It was used in tonic wines, toothpastes and popular drinks were named after it.

It was only scheduled as a proscribed drug a little under a hundred years ago, and the history of that is tainted with the sort of legal institutional racism Blair keeps saying he is against in all its forms - that it made "negroes" frenzied sex fiends.

The history of heavy addiction, and the dangers to health of tainted and constrained supplies all stem from its prohibition as a useful stimulant, not so much from any inherent danger in the drug itself. It is time a liberal world addressed these issues. If we're not going to prohibit absolutely everything that could possibly ever have any kind of effect on peoples' bodies or minds why should we choose these few substances? Cocaine use has been around for far longer than chocolate or coffee.