South Portland Police Chief Edward Googins is set to debate the leader of Maine’s marijuana legalization campaign in a public forum Wednesday evening in South Portland.

Googins has been a vocal critic of the effort to pass a citywide referendum Nov. 4 that would declare it legal in South Portland for adults 21 and older to possess small amounts of marijuana for recreational use.

The police chief has said the referendum would have no practical impact because marijuana will remain illegal under state and federal laws. But Googins also has argued that the proposal sends the wrong message about potentially dangerous drug use and that marijuana is not as harmless as legalization advocates say it is.

Googins will debate David Boyer, Maine political director for the Marijuana Policy Project, who argues that marijuana is safer than alcohol, that adults should not be punished for it and that prohibition of alcohol has failed to keep it out of the hands of youths.

Boyer has led Maine’s legalization campaign, which successfully got a legalization ordinance passed in Portland in 2013 and is now pushing for passage of referendum questions facing South Portland and Lewiston voters on Nov. 4. The two referendums are seen as a test of Mainers’ support for legalization and a prelude to a statewide referendum campaign, possibly within the next two years.

The debate will take place from 7 to 8:30 p.m. in the South Portland High School auditorium.

On Tuesday, Boyer issued a news release with a public challenge for Googins that Boyer said would prove marijuana is safer than alcohol.

“In order to prove once and for all that marijuana is less harmful than alcohol, marijuana initiative proponent David Boyer is challenging South Portland Police Chief Edward Googins to a drug duel,” the news release says. “Boyer will be in the Mill Creek Park gazebo at high noon on Wednesday prepared to take a hit of marijuana for every shot of alcohol consumed by Googins to see who will be the last man standing for a previously scheduled debate for 7 p.m. that evening.”

Googins dismissed the idea of such a challenge and said Boyer was simply trying shift attention away from the impacts of marijuana.

“They (marijuana and alcohol) are both bad, and they want the focus to be away from marijuana,” Googins said. “This is their playbook.”