Jim Borghesani, a cannabis consultant who helped lead the pro-legalization ballot committee, said the lack of significant data on widespread harm proves legalization is working. “We’re not comparing this to some minor concerns. We’re comparing this to apocalyptic predictions by opponents of carnage on the streets,” he said.

Some marijuana proponents compare it to alcohol. “Roughly 15 percent of the population that drinks alcohol becomes addicted to it, so that’s not a good thing and we deal with that very poorly, but we also accept it in the face of having alcohol available to the other 85 percent,” said Jordan Tishler, a cannabis doctor at inhaleMD and president of the Association of Cannabis Specialists.

Northampton Police Chief Jody Kasper, who has two marijuana stores in her city, said the real test of legalization could come years from now. “What we’re seeing is a change in culture in how people feel about marijuana,” Kasper said.