Stoned Lady 150x120.jpg
Updated Thursday at 10:32 a.m. with additional analysis of the arrest spike in Nevada.

After Nevada enacted a strict "per se" law restricting the amount


Marijuana DUI Law Impact Remains Unclear Despite Analysis of Arrest Statistics (UPDATED)

Stoned Lady 150x120.jpg
Updated Thursday at 10:32 a.m. with additional analysis of the arrest spike in Nevada.

After Nevada enacted a strict "per se" law restricting the amount of THC motorists are allowed to have in their blood, drugged driving arrests increased a whopping 76 percent statewide. But when a similar policy took effect in Ohio, arrests there decreased by a modest 4.8 percent. Such is the conflicting data recently presented by NORML, which further muddies the debate about Washington's proposal to legalize marijuana and start treating stoned drivers like drunks.

I-502 will be on the ballot this November, and, in addition to legalizing, taxing, selling weed in state-run stores, the measure proposes a limit of 5 nanograms of THC per milliliter of blood for drivers over 21, and zero tolerance for minors. The 5 ng/ml figure is supposed to be "roughly analogous" to the .08 standard currently in place for alcohol, but critics claim it's far too low and could make legal driving impossible for habitual tokers.

The controversy was the subject of dueling feature stories in Seattle Weekly and The Stranger earlier this month, and the Associated Press followed up over the weekend, writing about a "stoned driving epidemic." (Be afraid!) None of the articles, however, offered any hard data about whether THC blood limits translate to increased arrests and prosecutions.

While reporting the feature in Seattle Weekly, I reached out to law enforcement agencies in several states with per se limits but could never get good, reliable information about the impact of such laws. In Ohio, for example, the State Highway Patrol said that prior to 2006 when their 2 nanogram limit became the law of the land, they didn't keep track of marijuana DUIs because such cases were simply classified under the broad umbrella of drugged driving.

Now, however, NORML (the National Organization for the Reform of Marijuana Law) has collected the little datathat is available and compiled the info into a handy chart.

Thirteen Per Se DUID States.jpg
Chart and Data by Russ Belville
"THC Blood" is active THC, the type that would be used under Washington's I-502. "THC-COOH" is the inactive metabolite, which is criminalized elsewhere but not Washington. To view a larger version of this image, click here.
The research is the work of Russ Belville, the organization's outreach coordinator and an outspoken proponent of I-502. Belville says his info was gleaned from the FBI's uniform crime reports, drugged driving research from NIDA, and NORML's own database on drugged driving laws nationwide.

But just like the dilemma I encountered in Ohio, Belville says the figures in his chart only reflect general drugged driving arrests -- motorists busted for being on a variety of controlled substances -- not just weed alone. It's possible to infer that fluctuations in the states' DUI caseloads were the result of their new per se laws, but the data is undeniably flawed.

"It's a completely wild guess," Belville says. "We're only talking raw DUI numbers."

Taken with a sizable grain of salt, it makes interesting to look at how changes in arrest patterns were markedly different across the country. In addition the 76 percent spike in Nevada*, Indiana drugged driving arrests shot up 33 percent after adopting a per se THC blood limit, while Pennsylvania, Georgia, and Iowa all saw modest single digit increases. Five states had single digit decreases in drugged driving arrests.

Belville says he undertook the project with the goal of "punching a hole in the scaremongering around I-502" but the results could be used to buttress arguments on both sides of the issue. (As Mark Twain famously said: "There are lies, damned lies, and statistics.) Even so, Belville maintains that a mandate from voters to end marijuana prohibition would be enough dissuade police from using felony DUIs to unfairly punish potheads.

"The caveat is none these states have legal marijuana," the NORML activist says. "Even if I-502 passes and our worse nightmare comes true and there's a huge rash of DUIs, there will be outrage from a public that voted for legal marijuana that says 'What's going on here? I thought we legalized that.'"

*UPDATE: Turns out the alarming arrest spike in Nevada might simply be the result of uneven record-keeping by the state's law enforcement agencies rather than zealous enforcement of the new THC blood limit. Here's a year-by-year breakdown of drugged driving arrests in Nevada via the FBI's uniform crime reports:

2001 - 8,824 Nevada DUIDs

2002 - 5,186 Nevada DUIDs*

2003 - Incomplete Data*

2004 - 9,133 Nevada DUIDs

2005 - 9,746 Nevada DUIDs

2006 - 11,060 Nevada DUIDs

2007 - 12,538 Nevada DUIDs

2008 - 14,445 Nevada DUIDs

2009 - 15,234 Nevada DUIDs

2010 - 13,412 Nevada DUIDs

As Belville notes, the comparatively low number of arrests in 2002 versus later years might be a bit misleading since only three state agencies supplied data to the FBI that year, compared to more than 30 in other years. The following year the feds decided the info was so unreliable it wasn't even worth publishing. When the Nevada cops finally got their act together and started supplying good stats to the FBI again in 2004, the new law was in effect. While it's likely the per se limit spurred an increase in arrests, it's not nearly the astronomical jump it might appear to be at first glance.

Follow The Daily Weekly on Facebook and Twitter.

comments powered by Disqus