Six years after federal law changes gave police new powers to compel suspected drug-impaired drivers to take roadside sobriety tests, watchdogs say the system has been ineffective, resulting in few charges.

But there is no consensus as to what should be done about it.

A B.C. technology company is producing what it says will be the first commercial marijuana-detecting breathalyzer, but a prototype is still a few months away from release and needs further testing.