"All of us owe George Soros a great deal of gratitude," said Keith Stroup, founder of the National Organization for the Reform of Marijuana Laws.
If the measure is approved in November, Massachusetts would become the 13th state to lift or ease criminal penalties on marijuana possession. The proposal would make having an ounce or less of the drug a civil offense punishable by a $100 fine.
A spokesman for Soros referred questions to Ethan Nadelmann, executive director of the New York-based Drug Policy Alliance. Soros's efforts to ease penalties for drug crimes have come through the alliance, where he is a member of the board of directors.
Nadelmann said Soros believes that the war on drugs is draining money and resources that could be better spent.
"He thinks the [ballot question] is a responsible initiative to reduce the over-reliance on criminal justice sanctions in dealing with marijuana," Nadelmann said. "Marijuana should not be a priority of the criminal justice system."
Soros is credited with putting financial muscle behind many of the state initiatives easing marijuana laws, backing efforts in California, Alaska, Oregon, Washington, Colorado, Nevada, and Maine from 1996 to 2000.
Critics say marijuana decriminalization sends the wrong message to young people, that using drugs carries few consequences. Not only are there health risks associated with marijuana, they say, but users often move on to more dangerous illegal drugs.
Gerard T. Leone Jr., the Middlesex district attorney, said the marijuana being sold on the street these days is more potent than that sold three decades ago.
"Decriminalizing marijuana is a slippery slope and sends the wrong message," he said. "Compounding this is the fact that users of marijuana are 10 times more likely to be injured, or injure others, in automobile crashes."
Leone said marijuana possession is already treated less stringently in the courts than other drugs.
