Can I fail a pot test after smoking?  After NOT smoking? Even in Boulder ???

Every blog addressing great words is especially fun in Boulder! We’re SMART. We have GREAT vocabularies, And we have an unquenchable desire for knowledge.  For many of us, that means learning more about our favorite drug, marijuana.  While not for everyone, it is certainly the drug of choice for some. and Boulder has long been pot-centric in many ways. Just as “shared knowledge is power,” we simply must know as much as possible about chemistry we introduce into our bodies.  That means for some of us, learning about urine testing for THC COOH. Do NOT panic! THC generally refers to Delta-9  tetrahydrocannbinol, the THC we are most interested in if we want to catch a buzz. While some of the other 105+ cannabinoids found in the pot plant are psychoactive, they are either very mildly psychoactive, or are present in such small quantities that  a buzz generally does not result. The recently famous “Delta-8 THC,” while highly psychoactive, is present in the plant in minute quantities. So practically, it is not a significant factor in getting high until someone is using some type of additional lab processing to increase the concentration (the amount) of Delta 8 THC being consumed. Reports vary as to whether or not the Delta 8 is stronger or weaker than Delta-9

Urine testing for pot is becoming a quickly vanishing method of testing employees for drug use. That is GREAT news! The quick and dirty (and cheap) urine testing for drugs (frequently a 13 drug poly-screen test) does not work! Not always. It produces false positives. It can label someone as using drugs on the job without considering whether or not there is actual impairment. The lab work can be error-prone, leading to “false-positives.”

woman in white coat holding black dslr camera

Science for Justice; Truth for Justice

Urine samples are still sadly in wide use as a fast, easy and cheap way to test for marijuana. Employers, Probation Officers, Doctors, some government jobs (that list is shrinking fast), and many others use poly-drug urine test kits to check for employee and others for sobriety. Marijuana is generally part of the list singled out for testing. Let’s be clear. We do NOT want impaired people performing dangerous tasks. Operating a table saw while smoking pot is simply a bad idea. Unless you have extra fingers!!! Even then it is a bad idea. We love our readers. ALL of them! And we love them being able to type with all of their fingers. As a guitar player I am not Jerry Garcia or Django Reinhardt. I’ll opt for as many fingers as I can. Six strings is more than enough for the other hand!

silhouette of person's hands forming heart

I have all 10 fingers, which Django and Jerry did not have. They just played better. A LOT better. Did they smoke pot? Whatever they did or did not imbibe, it apparently did them no harm! It is thought that Django may well have been a pot smoker.

Circular saws are great tools. Pot is a great drug and a great tool. They simply do not mix. How does that impact carboxy THC, (THC COOH)? First, the vocabulary.

THC & Table saws? Perhaps Not!

The pot problem is that the urine test is  mostly for Carboxy Tetrahydrocannabinol. THC-COOH. Although it is a form of THC, it is NOT psychoactive. Our psychoactive (it gets you high) and  generally sought after THC cannabinoid is the Delta-9 THC. While related to COOH, (carboxy THC) and also another of the 105 cannabinoids in the pot flower,  it has none of the psychoactive effects of any of the cannabinoids. It is also the cannabinoid that is stored in fat tissues of the body for weeks and sometimes months. So a failed urine drug test can mean that the person smoked or ate medicated edibles weeks or more before the test. There is no way to tell how “old” the THC-COOH is when found in the human fat cells. A person could eat THC candy to help sleep on a Friday night, and fail a urine test on Monday morning. OR, what’s worse, our happy camper might fail a drug test for pot a week after smoking. Or if our intrepid camper is very unlucky, they’ll be tested a month after a joint, and still fail the urine test. But the test is CHEAP! Possibly ruin a life? Yes. Possibly be scientific trash?  YES!   So in all fairness and scientific attention to specificity, testing urine for pot is cheap useless garbage. Was I clear? I said “cheap useless garbage.” and that is what I meant. Do we really want to ruin a person’s life because they might have smoked pot a week before a urine test, and with NO indication of any impairment? Perhaps the answer is “NO WAY!” We seek justice in our lives. We strive for fairness. We crave the proper application of science. We revel in great laboratory work. Why? To get at the TRUTH! Again, this is not legal opinion, just the sharing information!

Boulderites are incredibly smart, and therefore love words.

In Boulder, the TRUTH matters. We are scientifically tuned-in, we believe in intellectual honesty, and some of us like imbibing.  Intellectual honesty is honesty in the acquisition, analysis, and transmission of ideas. A person is being intellectually honest when they, knowing the truth, state that truth. Intellectual honesty pertains to any communication intended to inform or persuade.We Boulderites frown upon obfuscation, prevarication, trickery, mendacity, and deceptive behavior. Generally, whether or not there is agreement as to what the truth is, seeking the truth and preferring it is a shared Boulderite trait.   Some of us like the impact of marijuana on our systems. We like getting high. We like the other “unpleasant” side effects of pot. We also LOVE our lives, and want our glorious Boulder lives to be as long and as happy and rewarding as possible. For some of us, that includes smoking pot. Do I recommend it for everyone? Of course not! I think beyond “happy survival” there is little that I’d recommend for everyone. BUT I would choose it for myself?  Every day? Every minute? Every year? I don’t know! Those are personal decisions. The decision depends upon what we are planning to do next, what frame of mind we prefer for the moment, and keeping in mind that we do live in Boulder.

Roulder buildingThe Famous and Beautiful Boulder Theater


Imax Imax buildingIRRELEVANT THEATER PICTURE! I simply had to include this “movie art” picture. Life is better WITH this picture!

While watching the latest Mission Impossible might be excellent for stoned viewing, the drive to and from the movie theater can be extremely dangerous if stoned. The impairing impact of imbibing might last for 2-4 hours or more. So if one were to smoke after parking, and after removing the keys from the ignition (NO legal advice intended), one might be “legal” to drive after 3 hours. So pause for popcorn AFTER the movie, and you are likely OK to drive after the movie. NO GUARANTEES! Best is to have a “designated driver” who chooses to be the sober chauffeur, Sadly, this time line is not concrete, not written in stoned.

shallow focus photography of Gautama

There are no easy solutions. One could entirely forego the intake of any THC in any form. I hate that approach. GREAT suggestion: If you find yourself being urine-tested and have any concerns about what the test will show, get a blood sample drawn ASAP. You might want it later, and the evidence you may need is metabolizing rapidly. In legal vocab, the evidence is disappearing as we speak! Cases such as Greathouse and others spell it out in detail. (not legal advice). Do non-lawyers care about Greathouse? YES! Destruction of evidence is a most important area of law, and destruction of evidence evinces images of “hiding the ball,” and of other unethical evil behaviors. We want and demand fairness in our justice system. DEMAND!!! So while we might choose to not share the THC urine or blood results, we cannot have that option without the “second test” of blood. We are preserving our options.

SUMMARY of the key points: do not drive impaired. Urine testing for THC (pot) is fundamentally flawed. Refusing the test can be worse.

The cannabinoid in pot, of the 105 + cannabinoids, Delta-9 THC, is the cannabinoid most responsible for psychoactive impact. In other words, Delta-9 THC is what gets us a buzz.  That is the primary cannabinoid which gets us “stoned.” Because it gets you stoned, it is properly called “psychoactive.”

Maroon Bells:  Outside of Aspen, at Snowmass, the most photographed STONE site in Colorado!

The metabolite formed from Delta-9 THC is processed by the body, metabolized.  THC-COOH (carboxy THC) found in urine is inactive, having NO psychoactive effect. It is written THC COOH and read “carboxy THC.” It does not get anyone stoned. BUT, the metabolite is the chemical that may be found for weeks if not months after intake of the marijuana. The one that does get us stoned, Delta-9 THC, is metabolized to Delta-11 THC, and then THC-COOH. From Delta-9 to COOH might be accomplished by the body in 4-6 hours. The psychoactive Delta-9 is generally metabolized in under two hours.

SO, smoke early, smoke often, and smoke safely!!!  OR, don’t smoke, do not smoke often, and still smoke safely! Getting stoned can be fun, and it can also be dangerous. May I respectfully suggest that the “fun” option is preferable to the “impaired and driving” option?


  • 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.