Driving and Marijuana

As of this writing, marijuana use is legal in several states even though technically it is still unlawful at the federal level. There are 18 states, dating as far back as 1998, that have legalized the use of marijuana for medicinal purposes. And in the last election, two states (Colorado and Washington) legalized marijuana for recreational use. In the face of rapidly changing marijuana laws in the U.S. Driving Under the Influence (DUI) laws are lagging behind. Clearly, all forms of drivers ed, including online drivers ed, need to be updated to take into account this changing landscape.

A great example of this is in Washington state, where initiative 502 (I-502) was passed in 2012 legalizing the use of marijuana. The application of the DUI laws to those driving with THC (the active component in marijuana) in their blood will go through many iterations. Here are a few impacts to consider from these new laws:

  • Impairment measured in blood. The only current method of marijuana use detection is via blood analysis since Breathalyzers do not detect THC. This could cause a major privacy invasion as police could potentially force blood analysis more often.
  • Blood limits not well understood. If you are driving and the blood test shows over a five nanograms per milliliter (5 ng/ml) THC blood level, you can be considered automatically guilty in any driving incident regardless of actual fault. Unlike the alcohol limits, which were set after much research, the affects of THC on driving are not well understood and require much more research.
  • THC lingers in the blood. Unlike alcohol, whose affects can go away in a day or two, THC can be detected in the blood for up to 30 days. And the effects of impairment on driving over time are not well understood. It is possible for people to be legally impaired several weeks after marijuana use.
  • Marijuana impairs driving. All drivers should be aware of the fact that marijuana does have a negative impact on driving ability according to a study by the National Highway Traffic Safey Administration.

A few resources for those following this topic:

The impact of marijuana on driving and indeed marijuana use itself will continue to be a controversial topic for decades to come. We urge readers to be aware of both the safety consequences of driving and marijuana use as well as the changing legal issues.

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