An NPR member station
Play Live Radio
Next Up:
Available On Air Stations

Pot Debate Centers on Marijuana DUI Limits


Legal marijuana has been for sale since July in Washington ,but the debate over how much marijuana someone can consume before they are considered legally impaired continues. The legal limit for the active ingredient of marijuana, THC, before someone is considered too impaired to drive is 5 nanograms per milliliter of blood.

That standard was crafted into the state law based on a limited body of scientific study on the topic. The standard is based on “active THC”, rather than the THC that can build up in someone’s fatty tissues and be detected weeks after someone has injected marijuana. But the debate over whether that standard is too high or too low continues.

Spokane county Sheriff Ozzie Knezovitch says in his discussion with the State Patrol , he has learned that no one pulled over for impaired driving so far has tested above the 5 nanogram level:

Knezovich: “The highest level I’ve heard through discussions on this topic was a 3.8 and the trope that told the number to us said this individual was quote “baked”, so our concern is that you’ve set a level that is five, and we’ve never seen anybody at five yet.”

But ACLU attorney Allison Holcomb, who crafted initiative that legalized marijuana, says there is also concern that the standard be too low.

Holcomb: “But we will be watching because we would be concerned if any unimpaired drivers get caught up in the system.From an ACLU perspective here in Washington we have a very strong state constitution, we have much stronger restrictions on when law enforcement can stop people on impaired driving, there has to be evidence of impaired driving before you can take someone in for a blood test, so we don’t see this per se standard as changing officers action in the filed very much.”

There is some discussion that medical marijuana patients or others who use a large amount of cannabis regularly do not become as impaired as the occasional user because they are accustomed to the effects. Chris Marr of the liquor control board says more research on the topic needs to be done by an objective third party.

Marr: “And we have one of the premier medical research facilities in the state, the University of Washington. To bring them in to the discussion so they can appropriately survey the empirical evidence out there, and conduct some of their own studies, because right now, we are dealing anecdotal and unverified evidence.”

The impairment standard could be changed. Initiative 502 was written as a “living document”, and the legislature can make changes to specifics of the law.

”These comments on this topic were part of our “Budding business of marijuana special."

Steve was part of the Spokane Public Radio family for many years before he came on air in 1999. His wife, Laurie, produced Radio Ethiopia in the late 1980s through the '90s, and Steve used to “lurk in the shadowy world” of Weekend SPR. Steve has done various on air shifts at the station, including nearly 15 years as the local Morning Edition host. Currently, he is the voice of local weather and news during All Things Considerd, writing, editing, producing and/or delivering newscasts and features for both KPBX and KSFC. Aside from SPR, Steve ,who lives in the country, enjoys gardening, chickens, playing and listening to music, astronomy, photography, sports cars and camping.