Easthampton is now the fourth city in Massachusetts to vote to decriminalize the possession and use of psychedelic plants.
Seven city councilors voted in favor of a resolution on the issue Wednesday night, and two abstained.
Psychedelic substances like psilocybin mushrooms are still illegal under federal law.
But, arresting people for growing, possessing or using them is now "among the lowest law enforcement priorities" for Easthampton police.
The resolution does not authorize the commercial sale of psychedelics.
Councilor Owen Zaret, who co-sponsored the measure, said he expects more communities to follow suit.
"I do really hope that what I see to be happening — and that Easthampton I think is really lucky to be on the cutting edge of — is that this whole topic, this is the start of a movement," he said.
"These medicines are saving our neighbors from addiction and suicide," said James Davis, lead volunteer of the advocacy group Bay Staters for Natural Medicine. "If cigarettes and alcohol are sold at every corner store, then we should be allowed to produce and use these medicines to heal ourselves."
A request for comment from the Northwestern District Attorney's office, which prosecutes drug cases in Easthampton, was not immediately returned.