Gov. Mark Dayton said Thursday that chances of a medical marijuana bill passing during the legislative session are slim, as the bill would have to clear too many hurdles.

During a conference call with reporters, Dayton also said he is not convinced there is medical evidence that marijuana is an effective treatment for illness.

• March 14: Dayton: 'Certainly time' on medical pot bill

• March 11: Minn. medical marijuana talks at stalemate

• March 2: Minn. physicians ponder medical marijuana

The governor's comments come as medical marijuana supporters are pressuring him to help broker a deal that would prompt the Legislature to legalize medical marijuana in Minnesota.

Dayton said there is still some time for legislators to craft some sort of compromise between supporters of medical marijuana and law enforcement officials who worry about the ramifications of making any form of the drug legal.

But Dayton said law enforcement, the medical community and others have raised concerns about how it would be administered if the state allows it. He said there's little scientific evidence that marijuana is effective, and noted that the federal Food and Drug Administration has not approved it as medicine.

The governor also said an idea to establish distribution centers across Minnesota is folly as marijuana plants need to be transported, grown, cultivated and distributed.

"It's just not going to happen this session," he said of the bill.

Dayton said he's sympathetic with people who say they need medical marijuana to treat certain conditions. But he said as governor he must weigh the potential good of marijuana for some against the harm it could cause others. He suggested the failure to pass a new law would not create a great hardship.

"I'm told by law enforcement that you can buy marijuana in any city in Minnesota," Dayton said. "We have the distribution already set up. It's extra legal, and basically not a crime for people, or an extremely minor crime for people who possess an amount for personal use."

State Rep Carly Melin, DFL-Hibbing, spoke at a committee meeting on legalizing medical marijuana in the state on March 4, 2014. Matt Sepic / MPR News

Dayton later emphasized that he is not telling people who are sick or have sick family members to buy marijuana illegally.

On Tuesday, state Rep. Carly Melin, the chief author of the medical marijuana bill in the House, said the bill was stuck because law enforcement was not willing to compromise. Melin, DFL-Hibbing, suggested supporters should focus their time and efforts on lobbying Dayton. Those efforts started Thursday afternoon, when about 75 people protested outside of the governor's residence in St. Paul to urge Dayton to change his position.

Members of Dayton's staff invited the protesters into the governor's residence, where he met privately with 11 people. After the meeting, supporters said they will meet with the Health Commissioner and Dayton's Chief of Staff to discuss whether a compromise is possible.

Jessica Hauser, of Woodbury, said she gives medical marijuana to her son, Wyatt, who has intractable epilepsy.

"My heart is just really full of hope that our governor heard us loud and clear, and that he's listening to the needs of the patients of this state," Hauser said.

Even though medical marijuana supporters say they're hopeful a compromise could be found, they said Dayton did not offer any assurances. Melin downplayed the chances of changing the law this session.

"The fact of the matter is that we're not going to push a bill forward that isn't going to get signed into law," she said. "I personally have no interest in giving patients false hope that something could happen if it's not going to happen. I have no interest in passing a bill that results in no patient is getting helped. And I have been pretty clear about that all along."

Melin said she thinks there is enough support in the House Government Operations Committee to approve the bill. But she said she would not push the bill through the committee if it has no chance of becoming law.