Citizens of Denver in the US state of Colorado will be asked to vote on a measure banning officials from “spending resources to impose criminal penalties” for the use or possession of the psychedelic drug.

It marks the first-ever referendum in the US on the use of magic mushrooms, the BBC reports.

The measure is strongly opposed by Denver Mayor Michael Hancock and Denver District Attorney Beth McCann, as well as the federal government.

However, campaign group Decriminalise Denver argues that “no-one should go to jail, lose their children, lose their job, and lose their citizen’s rights for using a mushroom”.