"Drug use may be an evenly distributed activity, but drugdealing isn't."
Evidence? I certainly don't believe that one bit.
The FBI stats are all the evidence any sane person needs. But that's all just a grand conspiracy, right?
Just like 9/11 and AIDS.
For example, a person may commit a domestic assault while high on drugs but the victim refuses to press charges. The city attorney agrees to a plea bargain on the drug charges to avoid a court battle which may go either way due to the lack of a key witness. It saves the state/city money and gives the person the opportunity to get clean.
Most of the people sentenced for drugs are not first time offenders and have other charges. Many are habitual offenders who support their habit by burglary, shop lifting, and robbery. Getting them off the street reduces overall crime.