"Roadside screening" refers to a process where authorities test drivers on the side of the road to check if they are under the influence of drugs or alcohol while operating a vehicle.
The public therefore accepts the use of breath samples both for roadside screening and ultimately for the determination of blood alcohol levels. (bestimpaireddefence.ca)
Subsequent police investigation suggested signs and symptoms of impairment as well as a failed roadside screening test. (criminal-defence-lawyer.com)
A combination of roadside screening, subsequent breath samples and expert extrapolation suggested that she was well above the legal limit for alcohol consumption at the time of the accident. (slaw.ca)