Changes to Canada’s impaired-driving laws could leave people having to defend themselves in court even if they only started drinking alcohol after they stopped driving, lawyers say.

The changes, which took effect last month, make it a criminal offence to have too high of a blood-alcohol level within two hours of driving. There are exceptions for people who consumed the alcohol that put them over the limit after they stopped driving – but it falls on the motorist to prove that.

The two-hour rule means police no longer have to catch an impaired driver before they leave their vehicle. Officers can show up at a suspect’s home or workplace, or wherever else they may be, demanding a breath sample.

“These new changes are radical,” Calgary-based criminal defence lawyer Ian Savage told

“They’re going to make it … more difficult for the police and the prosecutors, and they’re going to make it more difficult for the average citizen. I don’t see any real benefit to these changes.”

Michael Spratt, a criminal defence lawyer based in Ottawa, says these changes were made because the government was attempting to eliminate a defence some motorists could use to avoid an impaired driving conviction.

“Before the police interacted with them they’d pull out a bottle of vodka and chug the whole bottle – so then they could say ‘Well, look, I blew over at the police station, but at the time I was driving I was completely sober,’” Spratt told, adding that it was “very rare” for this defence to be used in court and even less common for it to succeed.

By attempting to crack down on that unusual defence, the government is shifting the onus of proof to people who drove and then drank, requiring them to prove that they only became impaired after they stopped driving. This means hiring a toxicologist to provide expert testimony in court.

“You’re going to have to hire a blood-alcohol expert at your own expense, and a lawyer. That’s easily going to run you well over $10,000 to $15,000,” Savage said.

‘A legal form of carding’

Police also no longer need a reasonable suspicion of impaired driving in order to conduct a breath test of anybody with care and control of a vehicle. All they need is to have a breath-testing device with them and a legal reason to pull a vehicle over or interact with its driver.

“If they have a Breathalyzer on them, they can demand a sample at any time under any circumstances,” Spratt said.

That could lead to police officers setting up checkpoints in known high-crime neighbourhoods and breath-testing every driver who passes through – giving them the chance to gather other personal data as well.

“When police pull you over to administer this random, groundless test, they can ask you who’s in the car, where you’re going, they can question you,” Spratt said.

“It’s sort of like carding, but it’s now a legal form of carding.”

Savage raises another scenario: A driver who has been drinking at a bar and grabs an item out of their car an hour later. Even if that driver doesn’t so much as start the car before returning to the bar, a police officer who sees them retrieving the item would be able to give them a breath test by the letter of the law.

“There is going to be a significant increase in the number of random breath tests being done of motorists,” he said.

Refusing to provide a breath sample is a criminal offence itself, with penalties ranging from a $2,000 fine to a maximum of 10 years in prison.

Spratt expects non-Canadians living in Canada and people of visible minorities to be disproportionately affected by the changes to the law.

Because the maximum penalty for impaired driving was increased to 10 years in prison, impaired driving is now classified as a serious criminal offence under the immigration and Refugee Protection Act. This means that anyone working through the immigration process who is convicted of any impaired driving offence will be kicked out of the country.

“If you’re a non-Canadian citizen, even if it’s your first offence … a removal order will be entered. You will be removed from Canada,” Spratt said.