5 nanograms of THC for DUID in Colorado is a half-baked idea

Kevin JensenThe notion that we should set an arbitrary limit of 5 nanograms of THC per milliliter of blood to prosecute Colorado drivers under the presumption of DUID is flawed, half-baked, not supported by science and feels absolutely un-American.

Yes, this is the same driving regulatory proposal that died in the Colorado Senate not too long ago, but last Wednesday, just 48 hours after this same bill was defeated in the Senate, an amendment to H.B. 1317 approved by the Colorado House State Affairs Committee would set a 5 nanogram presumption limit for all drivers.


This same DUID standard has been rejected in Colorado multiple times in the past years, but this time, advocates for the standard have included provisions that would allow people caught over the 5 nanogram THC limit to argue in court that they were not impaired and try to prove their innocence — sounds a little backward, right?

But even this tactic to pass the 5 nanogram limit was killed by the Senate because they decided there just isn’t any science solidly backing an across the board set limit. Nonetheless, in order to placate police organizations and Colorado Deputy Attorney General David Blake, the 5 nanogram limit was added as an amendment to a bill establishing guidelines to regulate state-licensed marijuana shops last Wednesday.

FOX31 Denver reports “The Colorado Association of Chiefs of Police and the County Sheriffs of Colorado were so upset over the initial draft of H.B. 1317 that the groups were threatening to write a letter to Attorney General Eric Holder asking him to intervene,” if the amendments they wanted weren’t added.

First of all, what a bunch of tattletales.

Second, as Jacob Sullum points out, such a move would be an outrageous betrayal by officials who have a duty to enforce Colorado law, which now includes the legalization and regulation of marijuana as part of our state constitution.

The 5 nanogram limit itself is a poor solution to our perceived need of more protection against people getting behind the wheel while stoned, but it seems that Colorado law is already more than adequate to deal with this.

Executive Director of the Medical Marijuana Industry Group Michael Elliott says Colorado’s current law has “a 90 percent conviction rate (of DUIDs) and has led to a 19 percent reduction in traffic fatalities over the last four years.”

In addition, as Ed Wood writes, in Colorado, “more than 70 percent of the blood samples tested from drivers arrested on suspicion of driving under the influence of marijuana are below 5 ng of THC. Today, those drivers are charged with DUI, and many are convicted. Few of them would be charged or convicted under a 5 ng permissible limit.”

You see, Colorado’s current DUID law bans driving while impaired to the slightest degree, but we don’t have any set limit on how much THC can be in the blood before legally being under the influence of drugs.

Currently, if a law officer determining a DUID looks at the behavior of the driver and the circumstances of the arrest — like if they fail a field test with THC in their system — then the case can be made for a DUID.


With a 5 nanogram limit, this would all change, and may allow infrequent users who may be seriously impaired to get away with it, while simultaneously opening heavy medicinal cannabis users up to DUID prosecution when they may not even be impaired.

Driving under the influence should be determined by impairment, not by some standard backed by questionable science. You can’t pull somebody over and test their THC level like you can with alcohol — drug testing can only be done with blood drawn by a medical professional, with a delay of 1 to 3 hours along with it.

Even then the test is flawed since everybody’s tolerance, frequency with which they smoke and body type are all different, making it difficult to determine the actual impairment of the individual at the time of arrest based on a blood test alone.

I understand the appeal of a 5 nanogram limit. No, it’s not really backed by science, but it’s a quick fix and stoned drivers sound scary.

I am against impaired driving in any form and to any degree (which is already law in Colorado), but a 5 nanogram limit would unnecessarily criminalize the innocent while possibly letting actual offenders get away scot-free.

I’d rather we use something like an objective, roadside administered, reflex-testing video game to test actual driver impairment than operate under an arbitrary 5 nanogram limit presumption of guilt.

Content Managing Editor Kevin R. Jensen is a senior English major. His column appears Wednesdays in the Collegian. He can be reached at  kjensen@collegian.com or on Twitter @kevinrjensen.