The federal agency for traffic safety says there is “relatively limited research” to support the idea that THC levels in blood can be used as a measure of impairment. This calls into question laws that are set in some states which limit cannabinoid metabolisms.
In a draft document published last month, National Highway Traffic Safety Administration discussed mixed scientific findings regarding marijuana and driving. However, they questioned the concept of impairment tests that are based on THC levels in the person’s body.
The report states that “a number of states have established legal definitions for cannabis impairment per se, but there is relatively little research to support their relationship with crash risk.” The report states that “Unlike research consensus which establishes a correlation between [blood-alcohol content] and crash risks, drug concentration in the blood does not correlate with driving impairment.”
NHTSA cited certain studies which it claimed supported the idea that cannabis usage may increase the likelihood of traffic accidents. However, they also pointed out that additional research “didn’t find a significant correlation” between marijuana use and the way police assign blame for accidents.
The report’s point regarding per se THC limitations is consistent with comments made by a Justice Department research who stated that states might need to “get away from this idea” that marijuana impairment could be tested on the basis of the concentrations of THC within a person’s system.
Frances Scott, a physicist at the National Institute of Justice’s Office of Investigative and Forensic Sciences (NIJ), under DOJ, explained that “chronic users and infrequent users have different concentrations correlated with different effects.”
A recent federally-funded study also looked at this issue. It identified two different methods for more accurately testing recent THC usage which accounts for the fact metabolites can remain in the system of a person for weeks or even months after consumption.
NHTSA is also required to submit a report on research obstacles that prevent the development of a standard test for driving while impaired by marijuana.
The Department of Transportation was required to complete the report by November a data-google-interstitial=”false” href=”https://www.marijuanamoment.net/biden-signs-infrastructure-bill-promoting-marijuana-research-by-encouraging-access-to-dispensary-products/” rel=”noopener” target=”_blank”>under ‘a large-scale infrastructure bill/a>a> under ‘a>a>/a>under ‘/a>/a>under. The Department of Transportation was supposed to finish the report by November as part of a large infrastructure bill signed by President Joe Biden. However, they missed this deadline and it is unclear how long it will take.
A congressional report last summer for a Transportation, Housing and Urban Development, and Related Agencies bill stated that the House Appropriations Committee, ” , continues to support development of an objective measure to measure marijuana impairment and related field sobriety tests to ensure highway safety.”
According to a study published in 2019, those who drive with the legal THC limit, which is usually between two and five nanograms per milliliters of blood, are not statistically more at risk of being involved in an accident than people who don’t use marijuana.
The Congressional Research Service determined in 2019 that “marijuana use can impact a person’s motor performance and response time… Studies of the impact on a driver’s risk of being in a car accident have produced contradictory results with some studies finding no or little increased risk from marijuana usage.”
A study conducted in 2022 concluded that CBD-rich marijuana did not have a “significant impact” on the ability to drive despite the fact all participants had THC levels above the limit per se.
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The article Federal Agency Says there’s “Little research” Supporting Marijuana Driving Impaired Tests Based on THC Concentration first appeared on Marijuana Moment.
