Legal Marijuana Still a Challenge for Road Safety

The state of Washington is finding that more and more fatal car crashes involve drivers under the influence of THC. But legal limbo, lack of research, and spotty detection makes the question of what to do very hard to answer.

2 minute read

August 29, 2015, 9:00 AM PDT

By James Brasuell @CasualBrasuell


Amelia Havanec reports: "Among those involved in fatal car crashes in Washington, the amount of drivers under the influence of marijuana escalated dramatically between 2013 and 2014, according to a new report by the Washington Traffic Safety Commission (WTSC)." To be more specific, there "was a 48 percent increase in THC-influenced drivers involved in fatal crashes between 2013 to 2014."

Before jumping to conclusions about whether the escalation of pot smokers involved in car crashes, the study also offered an important caveat: "around half of the THC-positive drivers were also under the influence of alcohol, exceeding the state’s limit of a 0.08 blood alcohol content. Furthermore, the majority of the crashes took place in the first six months of the year, before recreational marijuana stores opened."

Havanec helpfully notes that federal prohibitions on the sale and use of the drug, along with a lack of science, make setting, and detecting, driving limits for the use of the marijuana difficult.

In a separate article for Governing, Sarah Beitenbach goes into more detail about the challenges of policing "high driving" in states that have legalized marijuana for recreational use. According to Beitenbach, "[a]t least 17 states, including Washington, have “per se” laws, which make it illegal to have certain levels of THC in one’s body while operating a vehicle, according to the National Conference of State Legislatures (NCSL). Under these laws, no additional evidence is required to prove a driver is impaired."

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