OTTAWA - It would be easier for police to make drivers blow into a breathalyzer to detect alcohol as well as test people for drugs under the government's new legal-marijuana legislation.

The Liberals appear to be using the occasion of legalizing pot to remake criminal provisions on drunk driving as well.

Proposed mandatory alcohol screening measures would allow police to demand a breath sample from any driver they lawfully stop - without first having a suspicion the person has been drinking.

The aim is to help police catch more drivers at the wheel with more than the legal limit of alcohol in their bloodstream.

Police would also be able to demand a saliva sample from a driver if they reasonably suspect the person has drugs in their body.

Telltale signs could include the scent of marijuana, unusually red eyes or abnormal speech patterns.