One of the things that economists know for sure (and there aren't many!) is that if you want less of something, tax it. I am pretty sure most economists would prefer a legalize and tax approach to drugs than our expensive, destructive, and unsuccessful "WAR ON DRUGS".
From today's NY Times, you should enjoy this short little take on how the costs of drugs are pushed onto poor people, without any compensation for it. Another reason to re-think a horrible policy, especially at a time when everyone is concerned about government spending.