Helena, MT: House and Senate lawmakers have advanced legislation, Senate Bill 13, amending the state’s implied consent law so that police may administer oral fluid tests to motorists suspected of being under the influence of drugs. The bill now awaits action from Republican Gov. Greg Gianforte.
The legislation stipulates, “A person who operates or is in actual physical control of a vehicle … is considered to have given consent to a test or tests of the person’s blood or breath for the purpose of determining any measured amount or detected presence of alcohol, or blood or oral fluid for the purpose of determining any measured amount or detected presence of drugs in the person’s body.”
The bill’s sponsor said that the results of oral fluid screens will be used for purposes of establishing probable cause only; a positive test result would be not viewed as prima facie
evidence of impairment.
Saliva testing can typically identify residual traces of THC for up to 48 hours following marijuana inhalation, a period of time beyond the window of cannabis-related impairment. However, this detection window is shorter than that associated with urine tests, which can detect the presence of the inert metabolite carboxy-THC for several weeks post-abstinence, or blood tests, which can detect the residual levels of THC for over a week in the blood of more habitual consumers.
Montana is among a handful of states that imposes criminal penalties for those who operate a motor vehicle with a detectable level of THC above 5ng/ml in their blood. NORML has long opposed the imposition of THC per se thresholds for cannabinoids in traffic safety legislation, opining, “The sole presence of THC and/or its metabolites in blood, particularly at low levels, is an inconsistent and largely inappropriate indicator of psychomotor impairment in cannabis consuming subjects.”
Additional information on oral fluid testing is available from the California NORML report, ‘Overview of Oral Fluid Testing.’ Additional information on cannabis, driving performance, and traffic safety is available from the NORML Fact Sheets on Driving and Marijuana.