A New Brunswick Mountie who made national headlines last month for publicly smoking medical marijuana while in uniform has been charged with assaulting a police officer.

Cpl. Ron Francis was arrested in Fredericton on Friday after police used a stun gun on him. He remains in custody after appearing in provincial court on Saturday, CBC News has confirmed.

The 21-year veteran of the RCMP has been ordered to undergo a 30-day psychiatric assessment at the Restigouche Hospital Center in Campbellton to determine if he can be held responsible for the charge against him.

He is scheduled to return to court on Jan. 6.

Francis serves with J Division in Fredericton, but is on medical leave. He suffers from post-traumatic stress disorder (PTSD), which he says is related to his work.

He received a prescription for medical-grade marijuana on Nov. 4, and says the drug has helped reduce his PTSD symptoms and calm him down.

Francis contends he should be able to smoke the drug while in uniform and did so publicly, defying RCMP bosses.

Mounties promptly seized his regular work uniform from his Kingsclear First Nation home on Nov. 28 and he turned in his red serge uniform the following day, as instructed.

RCMP were searching for him on Friday to conduct a "wellness check," due to concerns about his medical condition.

When officers were unable to find him, they asked Fredericton city police to assist.

Francis was located in the afternoon, when the alleged assault occurred.

RCMP Commissioner Bob Paulson has said he's embarrassed and disappointed by the case. The force had tried to discourage Francis from going public, Paulson told a House of Commons committee last week.