Cannabis-Impaired Driving: A Common Sense Approach
It’s important to remove impaired drivers from the road without unfairly implicating the unimpaired. With per se limits, that involves establishing a direct and parallel relationship between blood levels of THC and levels of impairment. Using the data from DUI arrests, researchers have studied this very relationship. Overall, they find that per se laws face many challenges when cannabis’s metabolic factors are taken into account. Unlike alcohol, cannabis is stored in the fatty tissues of the body. This characteristic means that cannabis compounds, including the psychoactive THC, store and are detectable long term, up to a month or longer of abstinence. Research on frequent and long-term recreational cannabis users finds that, since cannabis stores in the fatty tissues of the body and can be released long after sobriety, chronic users maintain a certain amount of measurable THC in their plasma at all times, even while sober, sometimes exceeding the typical per se standard of 5 ng. In fact, NHTSA found specifically that “THC levels of a few nanograms per milliliter (ng/ml) in blood can result …from chronic use where no recent ingestion has occurred and no impairment is present.” In a state with per se limits, such drivers, while not impaired, would be assumed impaired and prosecuted under per se laws, without evidence of impairment.
Lansing, MI, USA
2 Hrs Ago Last Activity
3 Official Replies