Margaret Kemper, ex-wife of former prime minister Pierre Trudeau, has been charged with drunk driving.

Kemper, 55, was not present when the case was heard for the first time in an court in Ottawa on Wednesday.

Staff Sgt. Mike Laviolette said Kemper was charged after a vehicle heading north on the Vanier Parkway in Ottawa was pulled over in a routine traffic stop at about 10:30 p.m. on May 30.

Police allege they smelled alcohol from Kemper, the driver of the car. Laviolette alleges Kemper failed a roadside screening and later failed a breathalyzer test at the police station.

She was charged with one count of impaired driving and one count of driving with more than the legal amount of alcohol in her system, and then released.

"It was very straightforward," said Laviolette. "There was nothing out of the ordinary. She was very co-operative."

Kemper, who lives in Ottawa, was married to the former prime minister from 1971 until 1984.

She later married real estate developer Fried Kemper, but that marriage also ended in divorce.

Margaret and Pierre Trudeau had three sons. Michel, the youngest, was killed in an avalanche in B.C. in November 1998.

Kemper was at Trudeau's bedside when he died in 2000 at the age of 80.

She is currently the honorary president of WaterCan, an organization that helps citizens of developing countries build a sustainable water supply and sanitation services.