Despite widely reported, oft-repeated claims by opponents of marijuana legalization, there was not a 32 percent increase in marijuana-related traffic deaths in Colorado between 2013 and 2014. Quite the contrary, an honest presentation of the data reveals that there was actually a slight decrease in drugged driving in Colorado following legalization.
The 32 percent increase claim comes from a report titled “The Legalization of Marijuana in Colorado: The Impact, Volume 3” issued by the Rocky Mountain High Intensity Drug Trafficking Area (RMHIDTA), a program of the federal Office of National Drug Control Policy — the so-called “Drug Czar,” which is required by law to actively oppose marijuana legalization efforts. 
Unfortunately, the claim is entirely made up.
Between 2006 and July 2013, the Colorado Department of Public Health and Environment (DPH) tested for THC in the blood of drivers involved in fatal car accidents in Colorado. If the driver had a THC level of 2 nanograms per milliliter (ng/ml) or higher, the death was classified as “marijuana related.” In 2012, there were 78 such deaths. Between January and July of 2013, DPH counted 71 such deaths — and then discontinued testing.
RMHIDTA resumed the testing in 2014, but dropped the threshold for what it counted as “marijuana related” by half — from 2 ng/ml to just 1 ng/ml. Unsurprisingly, the number of “positive” tests jumped up to 94.
While 94 is, in fact, a number that is 32 percent higher than 71, the report does not actually show an increase in drugged driving deaths — the report manipulated the numbers, and the public, by comparing 71 of one thing (drivers tested at 2ng/ml over just 7 months in one year) to 94 of a completely different thing (drivers tested at 1ng/ml over the full 12 months in another year). 
Buried in a footnote on page 23 of the report is the damning admission that approximately 17 of the 94 positive results in 2014 would have tested negative at the original 2 ng/ml levels — meaning that 77 drivers would have tested positive in 2014 had the test not been changed to produce the desired result. Thus, an honest comparison of full-year results from 2012 to 2014 — eliminating 2013’s part-year data — shows that there was actually a small reduction in “marijuana related” deaths, not a massive increase.
At the risk of beating a dead horse, it’s also worth noting that a blood THC level of either 1 ng/ml or 2 ng/ml does not indicate that the driver was actually impaired by marijuana at all. Indeed, it is not uncommon for THC to remain in the bloodstream at those low concentrations for days or weeks after the effects of marijuana have completely worn off. Colorado’s DUI law sets a standard of 5 ng/ml.
As the Legislature considers marijuana legalization in the coming weeks, road safety should certainly be a consideration. Our current drunk driving laws do not set a clear standard for marijuana impairment; that should be changed. And law enforcement should be given appropriate training and tools for identifying impaired drivers and getting them off our roads.
But it would be a mistake to continue the failed policy of prohibition on the basis of a blatantly falsified study purporting to show that drugged driving increased following legalization in Colorado.
Dave Silberman
Middlebury
Editor’s note: Dave Silberman is an attorney in Middlebury. This article does not represent the views of any client.