Many books have been written about the societal harms caused by prohibition. Society and government did wisely repeal the Volstead Act after 14 years of experiencing the harm caused by prohibition. The same dynamics apply here. There would be no ruthless drug gangs if the illegitimate drug prohibition did not exist. The government has no lawful authority to tell the citizen what he may or may not put into his body.
There are countless examples over many decades of the prohibition corrupting the police forces. Because of the $ involved, and because cops are only human, many cops have become involved in the drug business. Pass all the laws you want to, they won't change that basic fact.
So your reasoning seems to be that because we won't repeal prohibition, it's OK to have the judiciary hold the police above the law. Sorry Andrew, that seems illogical as hell to me. The record clearly shows that since QI was concocted in 1967, things have only gone downhill for the relations between police and citizens.