Says Approach Is Not Based On Science, But On “Convenience”
Charges That Many State Laws Falsely Define Sober Drivers As “Intoxicated”
Washington, DC: So-called zero tolerance drugged driving laws, which classify motorists who test positive for trace amounts of illicit drugs or drug metabolites (non-psychoactive compounds produced from the chemical changes of a drug in the body) in their bodily fluids (blood, saliva, and/or urine) as criminally impaired, do not promote public safety and improperly define many sober drivers as “under the influence,” concludes a comprehensive report issued today by the NORML Foundation.
The report, entitled “You Are Going Directly to Jail — DUID Legislation: What It Means, Who’s Behind It, and Strategies to Prevent It,” is a detailed examination of statewide “drugged driving” laws and the quantitative role of cannabis consumption in on-road traffic accidents.
“Zero tolerance per se laws have little to do with promoting public safety or identifying motorists who drive while impaired,” the report states. “Rather, the enactment and enforcement of zero tolerance DUID (driving under the influence of drugs) legislation improperly defines many sober drivers as ‘intoxicated’ solely because they were found to have consumed a controlled substance – particularly marijuana – at some previous, unspecified point in time.”
It continues: “This approach is not based on science but on convenience. Zero tolerance per se laws define a new, driving-related offense that is divorced from impairment. In their strictest form, any driver who tests positive for any trace amount of an illicit drug or drug metabolite (i.e., compounds produced from chemical changes of a drug in the body, but not necessarily psychoactive themselves), is guilty per se of the crime of ‘drugged driving,’ even if the defendant was sober.
“In the case of marijuana, these laws are particularly troublesome. THC, marijuana’s main psychoactive constituent, may be detected at low levels in the blood of heavy cannabis users for 1-2 days after past use. Marijuana’s primary metabolite THC-COOH, the most common indicator of marijuana use in workplace drug tests, is detectable in urine for days and sometimes weeks after past use – long after any psychoactive effects have ceased. Consequently, under ‘zero tolerance’ per se laws, a person who smoked a joint on Monday could conceivably be arrested the following Friday and charged with ‘drugged driving,’ even though he or she is no longer impaired or intoxicated.”
To date, eleven states have enacted zero tolerance per se laws for controlled substances: Arizona, Georgia, Illinois, Indiana, Iowa, Michigan, Minnesota, Pennsylvania, Rhode Island, Utah, and Wisconsin. Of these, Arizona, Georgia, Illinois, Indiana, and Utah forbid drivers from operating a motor vehicle with any detectable level of a controlled substance or its metabolites in one’s bodily fluids. Similar laws are pending in additional states.
Regarding cannabis’ potential impairment of psychomotor skills, the report finds: “While it is well established that alcohol increases accident risk, evidence of marijuana’s culpability in on-road driving accidents is less understood. Although marijuana intoxication has been shown to mildly impair psychomotor skills, this impairment does not appear to be severe or long lasting. In driving simulator tests, this impairment is typically manifested by subjects decreasing their driving speed and requiring greater time to respond to emergency situations.
“This impairment does not appear to play a significant role in on-road traffic accidents when THC levels in a driver’s blood are low and/or THC is not consumed in combination with alcohol. … [F]rom the available research, it is apparent that cannabis’ adverse on-road impact is hardly so great as to warrant the passage and enforcement of zero tolerance per se DUID legislation, which would unavoidably classify many sober cannabis users as ‘impaired’ and threaten them with criminal prosecution.”
Commenting on the report, NORML Director Allen St. Pierre said: “We all support the goal of keeping impaired drivers off the road, regardless of whether the driver is impaired from alcohol, cannabis, or other drugs. However, these zero tolerance laws are neither a safe nor sensible way to identify impaired drivers; they are a cynical attempt to misuse the traffic safety laws in order to identify and prosecute marijuana smokers per se. They should be opposed by citizens and lawmakers alike.”
PDF versions of the report are available at: