if there was a viable equivalent of a breathalizer for checking drug impairement I'd be less opposed and am also concerned whether the testing is to determine if you have any drugs in your system, or if its to test for a significant enough level to warrant accusing you of being impaired (and how that level has been determined) picture you're at a party where half the people are smoking up and you're not but are breathing the air... you leave, blood tests positive for cannabis, and $10,000 in defence fees later maybe you don't lose your license and go to jail... even though you "just said no"... alcohol doesn't end up in your system just by being in the same room also some drugs linger in the system... what if you do something recreationally on the weekend and then still test positive for it on tuesday morning while driving to work mainly I just don't like the idea of the police being able to say "according to the Doppleghan/Struess system of impairement evaluation I believe you are on drugs and therefore request a blood and urine sample" bad luck for people with a stigmatism of the eyes that doesn't allow their eyes to open fully... or people with allergies... or a head cold... or a speech impediment... or who take painkillers for a chronic disorder... or like patchouli oil or burning incense... or simply have a nervous disposition... or... or... or... sounds like a sweet cash cow for the court systems anyways