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Washington state marijuana legalization comes with bitter pill of DUID conviction risk at 5 nanograms of THC

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Over the weekend, I learned that last month’s Washington state successful marijuana legalization referendum came with the bitter pill of a risk of guilt for driving under the influence of drugs with a THC concentration exceeding five nanograms per milliliter of blood. This information was available before the referendum voting date, but it is not possible for me to catch all essential news amidst the election season blur of Republicans and meat. Here is the Washington state law on driving under the influence of marijuana, which incporates Washington’s marijuana legalization referendum language; I copied this statutory language from Westlaw.

Colorado, which also passed a marijuana legalization referendum last month, is also facing possible legislation setting a presumed level of unlawful THC content.

THC ordinarily stays in the bloodstream for over two weeks, which counters any wisdom to setting blood THC concentration levels that presume driving under the influence of drugs.

Moreover, daily medical marijuana users are going to have THC levels in their bloodstream always. The Marijuana Policy Project points to a study showing a 13 nanogram/mL blood THC level in a man who was not impaired. Criminalizing alcohol, THC and other drug levels makes no sense for impaired driving prosecutions, rather than prosecuting for impairment itself. Instead, the alcohol, THC or drug level should, at worst for the defendant, be part of the totality of the circumstances in determining whether the driver was unlawfully impaired by alcohol, marijuana or drugs. To do otherwise violates criminal defendants’ right to due process of law under the Fifth and Fourteenth Amendments of the United States Constitution.

The MPP article addresses states setting THC blood concentration limits on drivers as follows:

"Nevada and Montana have per se DUID laws. In Nevada, a driver is per se guilty of DUID if the level of THC in his or her blood exceeds two nanograms per milliliter (ng/mL) of blood. In Montana, the per se limit is five ng/mL for patients. In 2011, the Colorado Legislature debated setting a five ng/mL per se limit similar to Montana’s, but decided against it due to a lack of scientific consensus and concerns that many legal medical marijuana users’ blood would exceed the THC limits even when they are not legally impaired."

California NORML has an article on the relevance of THC blood content levels to impaired driving here.

One important decision that drunk and drugged driving suspects must make in states that allow them to refuse a breath, blood or urine test for impaired driving, is whether to refuse the test. Where I practice, the loss-of-license risks can be severe for refusing the test where the police officer has sufficient grounds for requesting the test. It is critical to consult a lawyer in advance of an arrest for influenced driving, to help decide whether to take such a test if ever asked to do so.