Proponents of marijuana legalization have advanced plenty of arguments in support of their drug of choice — that marijuana is less dangerous than legal substances like cigarettes and alcohol; that pot has legitimate medical uses; that the money spent prosecuting marijuana offenses would be better used on more pressing public concerns. While 13 states permit the limited sale of marijuana for medical use, and polls show a steady increase in

ANNAPOLIS — When a police officer asked her what she was doing behind a van in the park, Pamela Hughes told him the honest truth. “I said I was smoking a cannabis cigarette,” she said. She presented the stunned policeman with a written recommendation from her doctor and a copy of Maryland’s “Compassionate Use Act,” which reduces the penalties for possession of medical marijuana. “I honestly thought that I wasn’t