William McNichol has posted Toward A Rational Policy For Dealing With Marijuana Impairment – Moving Beyond ‘He Looked Buzzed To Me, Your Honor’ (McNichol, W.J., Toward A Rational Policy For Dealing With Marijuana Impairment – Moving Beyond “He Looked Buzzed To Me, Your Honor” 45 So. Ill. U. L.J. 1 (2020)) on SSRN. Here is the abstract: This paper examines how marijuana impairment is currently proven, especially in states where marijuana has been legalized under state law. Much of the currently used proofs, and in particular testimony of purported Drug Recognition Experts, and some legislatively imposed standards are scientifically unsound and their use should be discontinued or severely limited. It is recommended that development of a valid biochemical proxy for marijuana impairment should be a priority funding item in states where marijuana is legalized.