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Charles H. Williams,
Attorney and Counselor
at Law, P.S.
707 South Snoqualmie
Suite 4A
Seattle, WA 98108

Toll free:800-854-3458
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Marijuana is legal in Washington, but driving under its influence is not

In November 2012, Washington became one of only two states in the nation - the other state is Colorado - to legalize the possession of small amounts of marijuana for personal use.

As of 12:01 a.m. on December 6, 2012, Washington ballot Initiative 502 (I-502)became law, and now anyone over 21 years old can legally possess up to one ounce of marijuana. How non-medicinal users of marijuana can legally obtain the substance, however, is still a gray area.

While pro-legalization individuals celebrated their victory at I-502's passage, many failed to realize the significant burden they brought upon themselves. To garner support for legalization, I-502 sponsors knew a drugged driving provision would be a necessary selling point.

Tucked away in the initiative was a provision significantly reducing the proof required to convict a marijuana-using driver for DUI. Previously, to prove that a person was driving under the influence of marijuana in Washington, the government was required to present evidence that the marijuana appreciably affected the driver's abilities.

This required testimony on a variety of factors including driving behavior, post-arrest observations, field-sobriety test performance, the concentration of THC (the psychoactive chemical in marijuana) in the driver's blood, and government toxicologist expert opinion.

Driving under the influence of marijuana post-Initiative 502

Before I-502's passage, there was no presumptive level of THC intoxication. Under I-502's drugged-driving provision, drivers with five or more nanograms of THC per milliliter of blood can be found guilty of DUI, even if the THC did not affect their driving abilities.

The practical effect is that it is now much easier for prosecutors to convict drivers of being under the influence of marijuana. Whereas testimony regarding behavior was previously necessary, the government now only needs a toxicology result.

This could spell trouble for marijuana smokers, especially medicinal and other heavy users, who may be capable of driving normally while having higher than legal doses of THC in their bodies.

Even so, however, the police cannot randomly stop drivers to test their blood. There must still be an observed traffic infraction or a reasonable suspicion that the driver is under the influence.

Nevertheless, those drivers who choose to smoke marijuana should use extreme caution behind the wheel, as the consequences for DUI in Washington remain severe.

For that very reason, the medical marijuana community opposed I-502. Steve Sarich, a medical marijuana user and head of the "No on I-502" campaign, called the initiative's legalization provision a "Trojan horse" for the stricter impaired driving provision.

In lifting the state prohibition on the possession of marijuana, the voters of Washington have unintentionally shot themselves in the foot when it comes to drugged driving. Only time will tell how the new law will actually play out.

If you or a loved one has been arrested for driving under the influence of marijuana, contact an experienced DUI defense attorney to discuss your situation and your legal options.

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