This is probably an important question, as a third of U.S. states are currently experimenting with some type of medical marijuana law. At the same time, the DOJ is cracking down on the drug’s use, and the DEA continues to claim that pot has no medical value. This is a claim, of course, that many deny.

Our friends over at PBS NewsHour featured this video last night, exploring the science behind the issue. It traces the stories of a 27-year-old epilepsy patient who says her seizures have stopped since using medical marijuana; a doctor who points out the need for science-based evidence, not a “hodgepodge of state laws and anecdotal stories; and scientists who are racing “to unlock the mysteries of the receptors by using newly created synthetic drugs, instead of tightly restricted whole cannabis.”

The clip is from Montana PBS’s Anna Rau, who produced a full-length documentary on the topic. Montana has had a medical marijuana law on the books since 2004, when 62 percent of Montana voters approved the initiative. The state legislature recently passed a bill repealing the law, but Gov. Brian Schweitzer [D] promptly vetoed it, arguing it was against the will of the voters. Schweitzer did say he would approve other measures that would more strictly regulate the medical marijuana industry.