A New Brunswick Mountie who made national headlines for smoking medical marijuana while in uniform last year changed his plea to guilty to three charges as a three-day trial was set to begin.

Cpl. Ron Francis, a 21-year RCMP veteran who was serving with the J Division in Fredericton, had been facing a total of six charges.

He was set to stand trial on six charges before he pleaded guilty to two counts of assaulting fellow officers and one count of breaching an undertaking to not possess or consume alcohol and non-prescription drugs. Three other charges were withdrawn. He had pleaded not guilty to all six charges earlier this year.

Cpl. Ron Francis, a 21-year veteran of the RCMP, will be sentenced on Nov. 3 in provincial court in Fredericton. (CBC) Francis, a Maliseet from Kingsclear First Nation, entered the Fredericton provincial courthouse on Wednesday holding a single feather.

All the charges stem from an alleged confrontation with fellow RCMP officers and Fredericton police officers who arrested him on Dec. 6, 2013, on a mental-health warrant and a second incident in January 2014.

Another resisting arrest count was one of the charges that was withdrawn.

Francis was emotional during the proceedings Wednesday. His sentencing hearing was scheduled for Nov. 3.

Focus on healing

Francis, who is still on medical leave from the RCMP, says he is focused on healing, and hopes his treatment will include guidance from a native elder.

T.J. Burke, his defence lawyer, hopes Francis will receive a conditional discharge.

Burke has previously questioned the RCMP's motives for seeking a psychiatric assessment of his client.

Burke questioned whether the RCMP was trying to stop Francis from taking his case to the media again, but RCMP said Francis was arrested because officers were concerned about his well-being.

Francis says he suffers from work-induced post-traumatic stress disorder (PTSD) and has a prescription for medical-grade marijuana.

He has publicly argued he should be able to smoke the drug in uniform, and has accused the RCMP of trying to force members with PTSD to quit.

The RCMP stripped Francis of his uniform and placed him on medical leave in November.

Francis contends the national police force needs to change its policies and provide more resources to officers.

In January, the RCMP offered to pay for him to go to a treatment facility in Powell River, B.C., for three months.

Francis agreed, but left the facility after three days, saying he couldn't get settled and felt he was being watched.