At least one DUI defense attorney is already making news by claiming he intends to challenge the 5 nanogram THC level passed in Initiative 502.  The claim is that the level violates Equal Protection provisions in the constitution.

The challenge isn’t new.  This was already tried in Nevada in 2002 when they passed their DUI marijuana law.  The Nevada state supreme court rejected the argument.  Interestingly, Nevada’s law is much more stringent that Washington’s new law.  Nevada banned 2 ng THC in blood and 5 ng Carboxy-THC in blood.  Washington’s per se level is 5 ng THC and there is no limit on carboxy-THC.  (The new Washington law actually says carboxy-THC is inadmissible.)

The full text of the Nevada case is here: Williams v Nevada (2002)

The defense argument is also very similar to what our own State Supreme court rejected in State v. Franco in 1982.  While the drug at issue in Franco was alcohol, the argument was the same: “How can someone know what an illegal amount of drinking is when it varies from person to person?”  The court concluded that drivers had sufficient information that impairment from alcohol varies but drivers have a duty to figure it out and not be impaired or exceed the legal limit when driving.

The combination of the two cases is compelling:  There is no constitutional right to smoke marijuana, so prohibiting any level of THC is constitutionally defensible.  The kenetics of how quickly or slowly marijuana is eliminated from a person’s system are the responsibility of the driver. 

Moral of the story:  Keep of the Grass LONG before driving!