Study: Legal limits for pot and driving are arbitrary, unsupported by science

Research conducted by the AAA Foundation for Traffic Safety has found the number of fatal crashes by drivers who had used marijuana doubled in Washington state after the drug was legalized.  Despite that finding, AAA reached the conclusion that legal limits for motorists who have smoked pot are arbitrary and unsupported by science, meaning police could possibly let impaired motorists go free, while others might be wrongfully convicted of impaired driving.The above video of traffic stops by police in Carol Stream, Illinois was obtained by AAA 

Marijuana use became legal in Washington state for those over 21 in December of 2012. The AAA Foundation analyzed drug tests and fatal crashes and came up with the following data:

• The percentage of drivers involved in fatal crashes who recently used marijuana more than doubled from eight to 17 percent between 2013 and 2014.
• One in six drivers involved in fatal crashes in 2014 had recently used marijuana, which is the most recent data available.

While AAA does not take a stance on whether marijuana should be legalized, the organization says it’s devoted to efforts aimed at the creation and enforcement of laws that help ensure the safety of motorists.

“Given the findings of this new research, our advice is that nobody should drive after recent marijuana use, and law enforcement should have a fair and educated approach for dealing with those who do,” said Kevin Bakewell, Senior Vice President and Chief Public Affairs Officer for AAA – The Auto Club Group.

NORML, a national organization devoted to the reform of marijuana laws, has taken a stance that while marijuana is considered by most experts to be safer than alcohol and many prescription drugs when it comes to driving, responsible pot smokers never operate motor vehicles while impaired.

AAA Foundation found fault with the legal limits some states have created to address marijuana driving impairment and cited the following evidence:

• Current science shows that drivers do not reliably become impaired at a specific level of marijuana in the blood. Depending on the individual, drivers with low levels of THC in their blood may be unsafe behind the wheel, while others with relatively high levels might not be impaired. This finding is very different from alcohol, where it is clear that crash risk increases significantly at higher BAC levels.
• High THC levels may drop below legal thresholds before a test is administered to a suspected impaired driver. The average time to collect blood from a suspected driver is often more than two hours because taking a blood sample typically requires a warrant and transport to a facility. Active THC blood levels may decline significantly and could drop below legal limits during that time.
• Marijuana can affect people differently, making it challenging to develop consistent and fair guidelines. For example, frequent users of marijuana can exhibit persistent levels of the drug long after use, while drug levels can decline more rapidly among occasional users.

As a result of its findings, AAA urges states to use more comprehensive enforcement measures to improve road safety. states should use a two-step system that requires a positive test for recent marijuana use, and most importantly, behavioral and physiological evidence of driver impairment. This system would rely heavily on two current law-enforcement training programs: Advanced Roadside Impaired Driving Enforcement (ARIDE) and the 50-state Drug Evaluation and Classification (DEC) program. These programs train law enforcement officers around the country to more effectively recognize drug-impaired driving.

“Marijuana can affect driver safety by impairing vehicle control and judgement,” continued Nasworthy. “Just because a drug is legal does not mean it is safe to use while operating a motor vehicle. Drivers who get behind the wheel while impaired put themselves and others on the road at risk.”

It would appear NORML is in agreement with much of AAA’s conclusions regarding the varying effects of marijuana use on individuals based on the article Cannabis and Driving: A Scientific and Rational Review, published in 2012.

The AAA Foundation plans to release additional studies focusing on marijuana impaired driving later this year.