The National Post reports in its Wednesday, Sept. 19, edition that when recreational cannabis becomes legal in Canada, most police forces will not be using devices that check a driver's saliva for recent drug use. The Post's Brian Platt writes that the Post contacted 15 of Canada's largest police forces, and almost all said they are still deciding whether to order the devices. Though the federal government approved one such device for use more than three weeks ago, many forces are waiting for it to approve a range of devices. Meantime, police will rely on a field sobriety test -- which can involve standing on one leg or tracking an object with your eye -- to screen for drug-impaired driving at the roadside. If drivers fail, police can bring them in for further testing. Roadside saliva-testing devices became legal in Canada after Bill C-46 passed in June. The Liberal government has touted them as an important new tool for cracking down on drug-impaired driving. Police, however, cannot order a model until it has been evaluated and approved according to federal standards. The evaluation process has dragged on for most of the year -- longer than government officials had anticipated.