Saskatchewan's highest court is putting the brakes on police randomly stopping people in private parking lots.

The Saskatchewan Court of Appeal says in a decision recently posted online that the province's Traffic Safety Act does not authorize police to conduct random stops in private parking areas.

The case involved a woman who was stopped by officers in a parking lot at a hotel in Humboldt in 2009.

The woman tried to take a roadside breath test, but couldn't and was charged with failing to provide a sample of her breath.

But Chief Justice John Klebuc said there was nothing unusual in the way the vehicle was being driven and no reason officers couldn't wait until she drove onto the road to check for a driver's licence and vehicle registration.

Klebuc said the detention, the demand for information and the sample impacted on the woman's liberty and privacy interests.

"While I am satisfied that (the officer) did not act in bad faith, he ought to have known that he was not entitled to detain the appellant and check for a driver's licence or vehicle registration, neither of which was required to operate a vehicle off highway on a private parking area," wrote Klebuc.