New Roadside Drug Test Promises To Provide Better Insight On Marijuana-Impaired Driving

Little Rock, Arkansas – As the marijuana decriminalization debate has given way to the legalization movement, the trucking industry seems to be on a collision course with how to adequately assess and address marijuana use among its driving workforce. The industry is wrestling with what to do in the face of more states legalizing cannabis for recreational or medicinal use. Marijuana use is still quite illegal for CDL drivers even in states which have legalized uses of the drug. However, the use of marijuana among truck drivers is on the rise.

Drug Use Among Truckers Is On The Rise

A 2016 United States Department of Transportation (USDOT) report revealed positive drug tests among truck drivers and other DOT security-­sensitive employees rose to its highest level since at least 2009. The report revealed the overall 2016 drug testing failure rate for all tests reported by certified labs increased to 1.98%, from 1.85% in 2015, the report said. The rate includes driver random, pre-employment, post-accident, “reasonable suspicion,” and return-to-duty drug tests. The most popular drug among truck drivers who failed tests was in fact marijuana.

Effects Of Alcohol Versus Marijuana

Some have argued the effects of drinking alcohol in excess mere hours before getting behind the wheel of a big rig are far more dangerous than the effects of THC. Dr. Denise Valenti, IMMAD LLC, argues this is not the case at all. “Marijuana affects self-awareness. A driver cannot accurately self-assess so they do not judge their impairment properly,” Dr. Valenti says according to a report. “I compare this to the permanent dysfunctions with Alzheimer’s disease.”

Dr. Valenti points to studies suggesting accident outcomes are worse for drivers who tested positive for marijuana-alone versus those who tested positive for alcohol-alone. According to the Washington Traffic Safety Commission, drivers testing positive for marijuana within four hours of a fatal crash are “six times more likely to have killed someone other than themselves compared to alcohol positive alone,” as reported in the agency’s 2015 report “Driver Toxicology Testing and the Involvement of Marijuana in Fatal Crashes, 2010-2014.”


In most cases the effects of marijuana can only be felt for no longer than 5 hours after oral ingestion. This makes trying to measure the impacts of the effects of cannabis a challenge. Administering accurate and timely testing is critical. Dr. Valenti says a potential testing breakthrough could be on the way soon.

New Roadside Drug Test Promises Better Marijuana-Impaired Driving Data

Dr. Valenti says researchers at the National Institutes of Health, among other experts, have developed a “simple goggle virtual reality system coupled with a cell phone and blue tooth response button to measure retinal dysfunction.” She also says, “We are finding mid peripheral vision impairments. This is essentially the ‘tunneling’ of vision often reported by marijuana users. The final version will be a quick, simple, objective, sensitive, specific test of marijuana driving impairment for law enforcement. This test will be threshold related and have a number value compared to a large normative data base. That test will take two minutes per eye.”

This test can be administered to the driver during a road-side inspection following a traffic stop or an accident. No doubt a test like the one Dr. Valenti describes would be challenged in the courts as an unconstitutional search. However, if it were to survive such legal challenges, it could provide more insight and data on the effects of driving under the influence of marijuana and could help more than just an industry better assess the marijuana legalization debate. It could help an entire country in the ongoing search of the appropriate balance between greater individual freedom and public safety.


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Comment (1)

  1. It’s ridiculous to believe that we as truck drivers give the government total control over us just to get a job!! The vision roadside test they give can give a false positive if you’re very tired. Of course giving the officials suspicion beyond a reasonable doubt will cause them to give you a urine test. We as truck drivers are THE ONLY ONES WILLING TO FO TO PRISON FOR THEIR JOBS!! Police can shoot someone dead on the street and they would NOT be asked to take a drug test. Someone can die on the operating table after a surgeon performs surgery and no test for him either!
    I understand that safety on the road is their main priority but at what price? Giving up all our rights for a job is ridiculous!!


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