The Supreme Court of Canada in Ottawa on July 21, 2011. (ANDRE FORGET/QMI AGENCY)

The Supreme Court acquitted a Quebec man Friday who fell asleep drunk in the driver's seat of his idling truck in 2009.

Donald Boudreault was drinking with a woman at her Jonquière, Que., apartment in February until morning, and she called a designated-driver service twice to take him home.

Boudreault sat in his truck to wait for the driver, and turned on the engine to warm up. But he fell asleep before the taxi service arrived.

The driver saw the man asleep behind the wheel of the truck and phoned the police.

Police arrested Boudreault and found his blood-alcohol was three times the legal limit. He was charged with care or control of a motor vehicle while impaired.

Boudreault was first acquitted at trial because the provincial court judge found there was no realistic threat to public safety since he had no intention of driving the truck himself.

His acquittal was later overturned in Appeal Court, and in a 6-1 decision the Supreme Court restored it.

The Criminal Code says it is an offence to operate or have the care of a motor vehicle while impaired in circumstances that create a "realistic risk" of danger to people or property.

However, the top court agreed with the provincial court judge.

"The risk of danger must be realistic and not just theoretically possible," the decision said.