The Alberta government is proposing updates to its impaired driving laws to comply with a court decision that found indefinite licence suspensions were unconstitutional.

Under Bill 29, introduced in the legislature Tuesday by Transportation Minister Brian Mason, people charged with impaired driving would face a 90-day licence suspension.

Once that period is complete, drivers can get their licence back if they join the ignition interlock program for one year. If they refuse, then their licence remains suspended for another 12 months.

Bill 29 also proposes changes to the Traffic Safety Act to add cannabis impairment to existing provincial legislation on impaired driving.

The changes are being made to ensure provincial legislation complies with C-46, the federal impaired driving bill.

"Our legislation is designed to dovetail and fit with the new federal legislation," Mason said, "and provide the administrative sanctions I think are necessary to reduce the incidence and use of any impairing substance."

The provincial bill adds impairment by cannabis, cannabis and alcohol, and illegal drugs, to the zero-tolerance rules for new drivers in the graduated licence program.

Under the federal government's Bill C-46, drivers with two nanograms (ng) of THC per millilitre (ml) of blood — but less than 5 ng — face a maximum $1,000 fine.

Drivers with five ng/ml, or 2.5 ng/ml combined with a minimum blood alcohol level of .05, face increased penalties for a first, second and third offence.

The federal government is planning to legalize small amounts of cannabis for recreational use by July 1, 2018.

Mason said the Alberta government is planning a public education program to educate people on the dangers of driving while under the influence of cannabis — especially to counteract the myth that people are less impaired when they smoke or consume marijuana.

"Part of the public communication that we need to undertake is to make people understand that impairment is impairment is impairment," he said. "Whether it's marijuana or alcohol, if you're impaired on the road, we need to do something to take you off the road."

Road-side saliva tests

The provincial government issues administrative penalties like licence suspensions for drivers who have .05 to .08 blood alcohol levels. A level higher than .08 is the threshold for police to lay a criminal impaired driving charge.

The federal government is currently testing a device that would allow police to conduct roadside tests for impairment by cannabis, cocaine and methamphetamine. These devices test the saliva of suspected impaired drivers.

Until those devices are approved, police can charge a suspected drug-impaired driver based on observed behaviour and standard field sobriety tests.

Police can then have a suspect provide a blood sample. Refusing to provide a sample is an offence under existing law.

In May 2017, the Alberta Court of Appeal ruled indefinite licence suspensions imposed in the province violated the Canadian Charter of Rights and Freedoms. That's because the practice ignored the presumption of innocence and the right to a fair trial before any punishment is imposed, the appeal court said.

The court was concerned an indefinite licence suspension period would encourage people to plead guilty simply to get their licence back.

The Alberta government had until May 2018 to fix the law.

Last month the province unveiled a proposed framework for marijuana legalization, calling for a minimum age of 18 to buy or use cannabis.

Additional legislation will be tabled by the provincial government on Thursday.

Other proposed rules included: