A new app called Canary costing $4.99, is trending. A person downloads their physical traits by taking a test of memory, reaction time, balance and time perception when sober and the app will compute if you are too impaired to drive safely when using marijuana. Sounds good until you consider that many jurisdictions do not require impairment to be convicted of DUI Drugs where there is a per se limit like the .08 for alcohol. Unlike a breathalyzer which measures the alcohol content of the breath/blood, the Canary is supposedly measuring impairment of motor skills and cognitive functions which should alert people to not drive a car but it does not measure how much marijuana is in a person’s system. In Nevada the per se limit for marijuana is only 2 nanograms (one billionth of a gram) for THC, the active ingredient in marijuana and/or 5 nanograms of the metabolite. Neither measurement has anything to do with impairment and in fact, experts have testified that NO ONE is impaired at those levels. Most at risk are those people who have medical marijuana cards and can use marijuana legally but are still subject to being DUI when they are above the limit, which would be virtually always.