If a cop rolls up on you, your car smells like weed, and you are unable to complete the roadside test, things could start looking really bad. A friend of mine was sitting in his car (not on or anything), not even smoking, and a cop shows up. Sees an empty pipe and gives him the test, he fails one of them and got his car taken away and went to jail. If anything, just try edibles. You can eat those in front of a cop. =)