Drug Testing - DUI - 6-17-12
(Legal Standards Defining DUID) "Nationwide, three different standards have been drafted in legislation defining what constitutes OUI [Operating Under the Influence] drugs: two 'effect-based' laws and one 'per se' law.45 The first effect-based law requires that an OUI drug motorist be rendered incapable of driving due to drug use.46 The second effect-based law requires a demonstration that an OUI drug motorist’s ability to operate a motor vehicle is impaired or that the motorist is under the influence or affected by an intoxicating drug while driving.47 Some per se laws set a limit on the amount of drug or drug metabolite in the driver’s system at the time of the arrest.48 However, there was a lack of consensus as to the particular levels. As a result, states with per se laws now employ a 'zero tolerance' per se law.49 This zero tolerance per se law prohibits motorists from operating a motor vehicle if there is any detectable level of illicit drug or drug metabolite in their body, regardless of whether the motorist operated the motor vehicle in an impaired manner."
Cafaro, Tina W., "Slipping through the cracks: Why can't we stop drugged driving," Western New England Law Review (Springfield, MA: Western New England University, May 10, 2010) Volume 32, Issue 1, pp. 43-44.