There are a couple of things that concern me here. Are they only testing for illicit drugs? In which case, why aren't they testing for legal drugs that impair driving also? Also, unless the law changed and I wasn't aware, driving under the influence of drugs is illegal - not driving with detectable amounts of drugs in your system. THC, for example, stays in your system a long time after its influence has worn off to any noticeable level. BAC has a line that demarcates safe and unsafe...why not other drugs?

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