Colorado’s lawmakers have already taken three cracks at crafting legislation to counter the supposed danger of driving while stoned. Now that state voters approved legalization last November, the calls have gotten louder to establish some sort of number-based standard, a line beyond which one is considered legally impaired due to smoking weed.
But wait a minute. Is stoned driving really a public menace? Seems there’s room for debate on that question. Many seasoned cannabis users say they drive just as well — maybe even better — while high than before smoking. And if marijuana really posed the kind of danger to driving as does alcohol, the toll would be bloody, and obvious — like it is with booze.
As the debate evolves, studies continue to be released that support both sides. When the Colorado Legislature takes up the question this year, it will be faced with two new studies, one which purports to show marijuana doubles the risk of automobile crashes, and the other which says that per-se THC blood limits just don’t work, reports John Ingold at The Denver Post.
It’s already illegal in Colorado to drive stoned, but currently the law is impairment-based. Prosecutors must prove that a driver accused of driving high was actually impaired for the charges to stick, if the driver chooses to take it to court.
That’s where the “per se” thing comes in. Bill sponsors this year will try again to set the limit at 5 nanograms per milliliter of THC — 5 ng/ml — but that’s a simplistic approach to a complicated question. The truth is, marijuana doesn’t impair to the extent or in the same way as alcohol, and the effects are much more variable across individuals.
Beyond all the other problems with per se THC limits — which were included in Washington state’s marijuana legalization measure approved by voters in November, but not in Colorado’s — the limits appear to be ineffective at controlling traffic fatalities, according to a study from Colorado University Denver professor Daniel Rees and Montana State professor D. Mark Anderson.
They looked at traffic fatality data from 16 states that have adopted blood limits for THC between 1990 and 2010, and found no significant statistical difference between states that did and did not have such laws.
“We cut the data a bunch of different ways and the estimate just came back zero, zero, zero, zero, zero,” Rees said. “All we can conclude is that, as currently implemented, they are not effective.”
All three previous versions of a marijuana DUI bill were stymied in Colorado by controversy over the 5-nanogram per se limit. This time around, the bill would allow defendants greater leeway to argue they weren’t impaired, even if over 5 ng.
Meanwhile, almost all medical marijuana patients in Washington state face the possibility of a DUI charge any time they get behind the wheel — even unimpaired — because of that state’s per se 5-ng limit which was built into the “legalization” law.