Pot impacts driving. Whether smoked, smeared or eaten we know that weed impacts/effects driving. Some of the changes may degrade driving. Impairment. Some changes from pot may not impair driving, but may impact it. Slower driving is a scientific reality. People argue about whether that is safer or more dangerous. Thus impact instead of impairment makes a better word choice.

The starting point, and what is most frequently misunderstood, is that cannabis impact does NOT follow the familiar “alcohol impairment” model. When we drink more booze, we get more intoxicated. When we smoke more pot, we get higher. If I smoke more pot, I’ll be higher than before I smoked the additional weed. BUT, and here’s the key, with alcohol, one person’s blood level will impact them similarly to that same blood level in someone else. We can have fair laws that say “if your blood alcohol level is above 0.08, we’re going call that “drunk driving.” Most people will exhibit comparable levels of impairment with comparable blood levels of alcohol. So laws based on the numbers make sense. Your Father’s 0.08 BAC is your 0.08 BAC. Fine for wine. Not for pot.

Here’s the rub. We have a current rush to get THC testing into the hands of LEOs (law enforcement officers). Many believe that if we measure the level of active Delta-9 THC in blood, we can get a fair measure of intoxication from the pot. Just like alcohol. So many are looking for measures from saliva, breath, and the like, to get quick easy “on-the-street” tools to measure the THC blood level, and from that to charge or not charge the driver with criminal offenses. BUT THC does not follow the well-known alcohol model. As I smoke more, and my active THC in my blood increases, I will personally show more impact. BUT the impact on me does not correlate, does not reveal the impact on another at the same blood level of active THC. So what works with alcohol by looking at the blood numbers simply does not apply to pot. Certainly counter-intuitive.

One person might be very stoned from a single toke of strong pot. Someone else, for a variety of reasons, of which experience and tolerance are only two, may show little or no impact from the same smoking. One person whose blood chemistry shows 5 ng/ml (nanograms per milliliter) cannot be compared to another person with the same test result. One person at 5 might end up as stoned as another with 150 ng/ml. So if I, as an individual, go from 5 to 25 ng/ml, I likely will be more stoned. But, and here’s the key, unlike alcohol, my 5 ng/ml cannot be compared to someone else’s 5. All 5’s are not created equal! Laws based upon blood levels are unfair, unjust, fail to provide equal protection, and are nothing but “feel good” laws.

SO if you smoke, know that:

1) pot certainly does impact behavior, including reaction time

2) most significant impact is seen from almost instantly with smoking, to perhaps hours later with edibles like candy

3) the most significant impact when smoking should have passed after 2-3 hours or so

Of course that varies with the person and with the pot. This is not legal advice, but shared common sense: if you imbibe, do not drive until your behavior, like reaction time, has returned to your personal “normal” behavior. If you plan to imbibe and drive, please remember that UBER is far cheaper than hiring me or any other competent or expert pot defense attorney. Generally, if you smoke, and avoid driving for 2-4 hours, your risk of driving impaired by pot are lower, and the more time that passes, the lower the pot impact.

Leonard Frieling
  • Senior Counsel Emeritus to the Boulder Law firm Dolan + Zimmerman LLP : (720)-610-0951
  • Former Judge
  • Photographer of the Year, AboutBoulder 2023
  • First Chair and Originator of the Colorado Bar Association’s Cannabis Law Committee, a National first.
  • Previous Chair, Boulder Criminal Defense Bar (8 years)
  • Twice chair Executive Counsel, Colorado Bar Association Criminal Law Section
  • NORML Distinguished Counsel Circle
  • Life Member, NORML Legal Committee
  • Life Member, Colorado Criminal Defense Bar
  • Board Member Emeritus, Colorado NORML
  • Chair, Colorado NORML, 7 years including during the successful effort to legalize recreational pot in Colorado
  • Media work, including episodes of Fox’s Power of Attorney, well in excess of many hundreds media interviews, appearances, articles, and podcasts, including co-hosting Time For Hemp for two years.
  • Board member, Author, and Editor for Criminal Law Articles for the Colorado Lawyer, primary publication of the Colorado Bar Assoc. 7 Years, in addition to having 2 Colorado Lawyer cover photos, and numerous articles for the Colorado Lawyer monthly publication.
  • LEAP Speaker, multi-published author, University lectures Univ. of Colorado, Boulder, Denver University Law School, Univ. of New Mexico, Las Vegas NM, and many other schools at all levels.
  • http://www.Lfrieling.com
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