Public safety officials in Minnesota have launched a criminal investigation following multiple claims that law enforcement officers got Occupy protesters high on drugs in a program examining the effects of street marijuana.

A state trooper has been placed on leave in connection with the allegations and the program has been suspended. One participant in the program said police got him "high as fuck".

The story was broken by independent journalists based in Minnesota who began recording officers picking up and returning protesters to a local park where the demonstrators have been camped out. Individuals repeatedly claimed that the police would provide them with marijuana, watch them smoke it, then observe their behavior. In several instances individuals who seemed sober when they left with police, return appearing to be under the influence.

"I got stoned with a couple cops," a protester who goes by the name Panda said on camera. He claimed he was walking near the park when an officer said he smelled of marijuana. This prompted Panda to walk faster, but then the police officer did something unusual and asked if he would like to smoke more. Panda said yes.

"I'm high as fuck," he said, following his alleged encounter.

Panda said the officers treated him to a meal after they smoked him out. "They bought me dinner," he said, claiming the police paid for a double cheeseburger from McDonalds. Panda said the police then timed how long it took him to eat the meal and observed how eagerly he ate once the burger was in his hands.

He speculated that the police wanted to "see how people act with the munchies".

Dan Feidt, an independent journalist with the Occupy movement, says he began noticing the activity two weeks ago. Feidt joined with other independent media outlets – including Rogue Media, Communities United Against Police Brutality, and Twin Cities IndyMedia – in documenting what was going on at the park.

Minnesota is among 48 states – as well as the District of Columbia and Canada – that participate in a so-called Drug Recognition Evaluator (DRE) program, aimed at helping officers learn how to spot impairment and troublesome drivers. The program began in Minnesota in 1991 and requires officers to perform evaluations on volunteers, generally recruited from the community, who are high.

The program does not permit officers to provide drugs to subjects, but that's exactly what Feidt's video suggests they did.

Forrest, another interviewee in the video, claims police got him high, but didn't test him because they suspected he was working with the journalists.

"They didn't test us this time. They just smoked us up this time," he said. Forrest was allegedly given a black box by the police complete with "weed, pipes and lighters." Forrest said he got high on the substance provided by police. "It was a whole bag of weed," he said.

The state patrol initially said there was "no evidence" to support the allegations made in the video but on Wednesday the Minnesota department of public safety issued a press release announcing that it had launched a criminal investigation into claims that a Hutchinson police officer provided marijuana to subject in the drug program. The allegation was made by an officer from another law enforcement agency. The DPS also announced that it was suspending the program.

Feidt says the program is consistent with police behavior he's observed at Occupy camps around the country.

"What we saw happen in many, many different cities was they would take people that had chemical dependency issues, they would take people that had mental illness issues and that kind of thing and they would basically drop them off at the Occupy site," Feidt told the Guardian.

He hopes the video will call attention to the war on drugs. "For me, the cruel and dehumanizing nature of the war on drugs has been a major issue for a long time," Feidt said. "There's public debate about this program that never really happened, so I'm really hoping that we can have a constructive debate and finally wind down this incredibly destructive system."