Town Hall, DC
A police officer pulls you over at a checkpoint and asks, "Have you been drinking?" Assuming he wants to know whether you have consumed alcohol in the last few hours, such that it might be affecting your ability to drive, you say no. "Not at all?" he asks. Well, you admit, you did have a beer the night before, whereupon he arrests you for driving under the influence.
If that scenario makes sense to you, you should have no problem with Michigan's new policy regarding driving and drug use. As recently interpreted by the state Supreme Court, Michigan law prohibits marijuana smokers from driving long after the drug's psychoactive effects have disappeared. A dozen states have similar policies, and federal drug officials think all of them should, which would in effect revoke or periodically suspend the driver's licenses of more than 25 million Americans.