Mark Stobbe (STOH'-bee), who worked for the governments of Manitoba and Saskatchewan, is accused of second-degree murder.
Stobbe was arrested in 2008, eight years after the body of his wife, Beverly Rowbotham, was found in her car in Selkirk, Man.
Stobbe had previously worked as a senior adviser to former Saskatchewan Premier Roy Romanow, and moved to Manitoba in 2000 to work for a provincial economic development committee.
The trial begins with two weeks of legal arguments, which are taking place without the jury present and cannot be reported.
Testimony is expected to begin in two weeks and the trial is scheduled to run until the end of March.