Jeffrey Paul Delisle jumps out of a Sheriff van after arriving at the provincial court in Halifax on February 28, 2012. Delisle, who was a naval intelligence officer, faces charges of giving secret information to a foreign entity. (REUTERS/Paul Darrow) Canadian spy's damage debated at sentencing hearing Spy case could have been far more embarrassing Halifax navy officer spied for Russia, willingly offered his services Military expert speaks on Delisle case

Sub-Lt. Jeffrey Delisle, a naval spy from Nova Scotia and the first person ever convicted under Canada's post-9/11 anti-terrorism legislation, will appear in court Thursday for sentencing.

Because nobody's ever been convicted under the Security of Information Act before, it's unclear what kind of punishment awaits the officer for selling Canadian secrets to Russia for $3,000 a month.

"The Crown has a strong incentive to seek a sentence sufficiently strong to act as a deterrent, whereas the defence is likely to seek leniency in return for pleading out," said Christian Leuprecht, a national security expert from Queen's University and the Royal Military College of Canada. "The eventual sentence rendered will establish legal precedent for any future arraignment under Canada's revamped Security of Information Act."

Delisle pleaded guilty in October to one count of breach of trust and two counts of sharing information with a foreign entity.

His two-day sentencing hearing starts Thursday. He may face life in prison.