Scientific Basis For Laws On Marijuana, Driving Questioned

WASHINGTON (AP) — Six states that allow marijuana use have legal tests to determine driving while impaired by the drug that have no scientific basis, according to a study by the nation’s largest automobile club that calls for scrapping those laws.
The study commissioned by AAA’s safety foundation said it’s not possible to set a blood-test threshold for THC, the chemical in marijuana that makes people high, that can reliably determine impairment. Yet the laws in five of th