One of the more startling realizations the film makes is how close the United States actually came to legalizing grass. The work of activists in the early '70s -- as well as the reaction to all of those white kids facing 50 years in jail for selling less than an ounce of pot -- helped persuade first Oregon and then nine other states to decriminalize marijuana. Federal penalties for possession were reduced, mandatory sentences abolished. Even Jimmy Carter got on board the decriminalization train as a candidate and then president -- until one of his Cabinet members was busted for using drugs. In the wake of the scandal a proposal to decriminalize marijuana died in Congress.

Drug policy in the next two decades, of course, devolved into the Reagan era -- frying eggs, "Just Say No" and zero-tolerance laws. "Grass" sums up the new, official arguments against weed in the '80s and '90s: "If you smoke pot, you will be a loser," and "Bad things will happen, but we don't know what they are." They're as laughable, if not more so, than the connection to communism. George Bush promises that the prisons will make room for new offenders, and law enforcement under the Clinton administration carries out more drug arrests than under any other president.

"Grass" ends with a parting shot of an activist at a pot rally standing next to a statue of La Guardia. It's a sadly mixed message. Here are the hard figures: There are 2 million inmates in prison right now, and 60 percent are there for drug offenses. The FBI reported that there were 695,201 marijuana arrests in 1997. Of those, 87 percent were for simple possession, as opposed to dealing or distribution. There have been 11 million marijuana arrests since 1965. The rate is now at an all-time high. And all pot activists have is a good argument, a handful of numbers -- and one brassy cold politician on their side.

"Grass" is currently playing in Chicago, New York and San Francisco. It begins a 20-city run over the next month on Friday.

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