HB 1325 sets a similar legal standard to driving under the influence of alcohol, establishing the amount of tetrahydrocannabinol (THC) a person can have in his bloodstream before he can be considered impaired while driving. THC is the predominant psychoactive chemical found in marijuana.
According to this new standard, anyone with five nanograms or more of THC per milliliter of blood can be considered an impaired driver, and therefore guilty of a DUI. The ratio for alcohol is more lenient, at eight nanograms per milliliter of blood.
According to Mason Tvert, director of communications with the Marijuana Policy Project, this policy does not entirely reflect the scientific reality of marijuana intoxication.
"Any standards created for determining impairment as it relates to driving should be grounded in scientific evidence, but the proposed level does not appear to meet that criteria," he wrote in a statement to Colorado Watchdog.