[HangnJudge]

Many are in jail for nonviolent drug offenses. Their only crime? Using an intoxicating substance other than alcohol or tobacco.

To do this, you must engage in criminal behavior to obtain drugs,
Consort with known criminals (pushers)
Often engage in criminal behavior to obtain money for drugs
Unless you are independently rich.

[adam_az]

" To do this, you must engage in criminal behavior to obtain drugs"

A victimless crimes, the act of which would harm no one if the activities in question were legal.

[Doctor Stochastic]

Or merely be accused of such crimes. People are sometimes held pending trial.