In Salon, Maia Szalavitz reports that the U.S. drug czar's office has cooked up a new scare campaign, telling everyone that pot causes schizophrenia. See ads like this one. Of course, despite the fact that marijuana use has increased at a fairly, um, healthy clip since the 1930s, the percentage of schizophrenics in the general population has stayed constant. So, you know, the link might not actually be that solid. Anyway, this would all be very humorous except that it has real effects on the credibility of serious health warnings. Methamphetamines, for instance, actually can cause psychosisbut, of course, no one is going to listen to a government that's already making hysterical claims about pot and mental illness.