A B.C. lawyer is calling proposed changes to Canada's impaired driving laws “unconstitutional.”

On Thursday, the federal government introduced legislation legalizing cannabis. At the same time, a proposal to create stricter rules surrounding drunk driving was tabled.

“If it passes Parliament, it will be one of the strongest impaired driving pieces of legislation in the world,” said Justice Minister Jody Wilson-Raybould.

The changes would allow law enforcement officers to demand breath samples from any driver they lawfully stop, without having suspicion that the driver has alcohol in their body.

Criminal defence lawyer Sarah Leamon believes that violates a section of the Charter of Rights and Freedoms that protests against unreasonable searches or seizures.

“When we get into the driver’s seat of a vehicle, we’re not doing away with all of our rights as a citizen. There still are charter rights that need to be upheld,” said Leamon.

Minister Wilson-Raybould disagreed, telling media she's "confident of the constitutionality of the mandatory roadside testing.”

If the proposal becomes legislation, Leamon says officers could pull over any vehicle on the road and target certain groups.

“I think you’re going to see a lot more younger drivers pulled over as well as visual minorities,” Leamon predicted.

The proposed changes still need to make it through Parliament before coming into effect.