Marijuana advocates to argue against Claire Levy bill setting THC driving-impairment limits

Update: Yesterday, the Cannabis Therapy Institute issued a press release that included an e-mail from attorney Lauren Davis criticizing HB 1261, Representative Claire Levy's bill to establish THC driving limits. Today, Davis has sent out a second e-mail acknowledging that some of her points in the initial note were "OVERSTATED and incorrect" and straightening out the facts. That doesn't mean, however, that she no longer objects to HB 1261.

"My conclusion is basically that if the legislature is going to set a per se limit, it needs to be a higher limit regardless of whether there's rebuttable presumption," she says. "Rebuttable presumption really shifts the burden to the defendant to prove that he wasn't under the influence, and the current standard allows the district attorneys to exercise prosecutorial discretion to determine if there's evidence other than just what the level is in a person's bloodstream as to whether they were driving while impaired, even to the slightest degree.

"That's what the law on driving while impaired is supposed to be about -- getting the drivers off the road who pose a danger because they're impaired. But there are a lot of cases where somebody's pulled over for speeding, which isn't a sign of impairment, and throughout the course of the contact, the cop is finding factors he's using to try to establish probable cause. But if you have just a 5 nanogram standard, which some patients are at all the time, they basically aren't going to be able to drive at all."

Below, find Davis's clarifying e-mail, complete with an excerpt from medical marijuana physician Dr. Bob Melamede, followed by our original coverage:

Lauren Davis e-mail clarification:

My statement in my previous email that there is no correlation between 5 ng and impairment was OVERSTATED and incorrect. You should be aware that there are some studies that show a correlation between 5ng and impairment, albeit with many, many caveats that I neglected to educate you about. So I am writing this to correct and clarify that statement. Please -- do NOT argue what I said to the legislature (that there are no studies showing this...), as it is wrong. Your argument needs to be much more fine-tuned.

If you scroll to the bottom, you will find information from Dr. Bob Melemede that more accurately sums up the studies and the point I got carried away making.

In the meantime, here is some other information, based on studies, for your information, which I cite in an attempt to explain why the legislature's proposed per se 5ng/ml is dangerous for patients. If the legislature is going to impose a per se limit, the limit needs to be higher:

To date, scientists have had difficulty assessing to what degree and at what levels cannabis is a causal factor in traffic crashes. Unlike alcohol, which affects the brain in a broad, non-specific fashion, drugs often operate on a much more complex level. And, cannabis, even more than other drugs, has a variable effect on impairment; this is apparently a well recognized and widely reported phenomenon. See The Influence of Cannabis on Driving, Prepared for Road Safety Division, Department of the Environment, Transport and the Regions, TRL Report 477, p3. This means that one person can be impaired when their blood plasma is at 5 ngml, but another individual (likely a patient or more regular user) will not show any impairment. Some international studies have found that "for up to two hours after a dose sufficient to give a 'high', there is impairment of the same order as alcohol at around the drink-drive limit," but those studies equate the dose to be 11 ng/ml, twice as high as the legislature is proposing. Id at 5. And, in a study sponsored by the US DOT,NHTSA, scientists concluded that driving impairment cannot be predicted on the basis of an individual's plasma concentrations of THC from a single sample.

"Interpreting the meaning of either drug/metabolite concentration in a single biological specimen..with reference to impaired driver performance is...an extremely difficult task." ICADTS Working Group Report - "Illegal Drugs and Driving" May 2000. "The interpretation of drug concentrations in biological fluids especially with regard to behavioral-effect requires some knowledge about the dose, the route of administration, the pattern or frequency of drug use, and the dispositional kinetics (distribution, metabolism and excretion) of the drug." See ICADTS report. The current legislative proposal does not account for these variables.

The point I was trying to make (albeit inartfully) is that relating absolute levels of THC in blood to an objective effect on a driver's ability to operate a motor vehicle is a very complex and difficult task, and one that will end up making criminals out of patients, based on inadequate scientific research. While a few studies show 5 ng correlates to impairment, there are many caveats to these findings (e.g. novice users vs consistent users/patients; metabolic issues; etc) And many other studies have concluded that there is NO statistically significant correlation between driving and impairment until a driver is at a higher level. In a laudable effort to ensure our roads are safe, the legislature is going to criminalize non-criminal conduct if it sets a per se level of 5 ng./ml.

The reason for the crime of driving under the influence is that a person's ability to drive is impaired. Current DUID laws allow police and prosecutors latitude and discretion to ensure that the law appropriately punishes those whose driving demonstrates impairment based on factors such as accidents, slow reaction times, etc., the real dangers the legislature is concerned about.


Subject: tolerance of heavy cannabis users and impact on driving skills

Hi All, in recognition of Colorado state's regulatory efforts to balance the need to protect it's citizens from impaired drivers, with an appropriate science-based protection of basic rights of the states medical marihuana patients, I am providing you with some peer reviews scientific articles that I hope will shape your views especially with regard to the 5ng/ml plasma THC level under consideration.

As you can readily see in table 2 of the attached article (the relevant portion shown below), the plasma THC concentration in the baseline control subjects (consisting of heavy cannabis users with an average age of 23.2 years) was already well above proposed limit for determining impairment.

Furthermore, the author's conclusions based on performance tests, were fully consistent with previous studies that demonstrated limited impairment caused by THC in regular cannabis users.

"Previous research has demonstrated that daily cannabis users are less sensitive to the impairing effects of Δ9- tetrahydrocannabinol (THC) intoxication on cognitive and psychomotor functions (D'Souza et al. 2008; Hart et al. 2001; Jones et al. 1981; Ramaekers et al. 2009) that have often been demonstrated in occasional cannabis smokers (Curran et al. 2002; Hart et al. 2002; Heishman et al. 1989; Lamers and Ramaekers 2001; Ramaekers et al. 2004; Ramaekers et al. 2006a), even when THC concentrations and levels of subjective high are similar (Ramaekers et al. 2009) This loss of sensitivity or tolerance to the behavioral effects of THC after prolonged use is believed to result from a change in pharmacodynamic response as evinced by CB1 receptor downregulation in large parts of the brain (Gonzalez et al. 2005). Alternatively, it has also been suggested that heavy cannabis users recruit alternative neural networks as a compensatory mechanism during task performance. Eldreth et al. (2004) and Kanayama et al. (2004) showed that compared with controls, cannabis users utilized additional brain regions to perform cognitive tasks, i.e., they compensated by working harder and recruiting compensatory networks."

The authors further concluded:

"THC did not affect performance of heavy cannabis users in the critical tracking task, the stop-signal task, and the Tower of London. These tasks have previously been shown to be very sensitive to the impairing potential of THC when administered to infrequent cannabis (Ramaekers et al. 2006a)."

They also noted:

"However it was interesting to note that tolerance was not apparent in all performance tasks. During divided- attention task performance, THC increased the number of control losses and reaction time and decreased the number of correct signal detections. Number of times that subjects lost control over the primary task (tracking) during this dual task performance appeared particularly sensitive to the impairing effect of THC." It is worth noting that sleep deprived subjects also show performance deficits in this task.

In view of the above data, the proposed regulatory plasma limit would unfairly single out sick medical marijuana patients as being impaired through the use of criteria that were inappropriate for this population. Furthermore, infrequent users will tend to have lower THC concentrations while being more impaired, thus defeating the very purpose of the regulations. In view of the above peer reviewed science, setting inappropriate THC plasma levels would needlessly harm patients and burden the judicial system.

It would make a lot of sense to test for both THC and alcohol to determine impairment. The 5 ng/ml would probably make sense when determined in conjunction with the alcohol level.

I have also attached an study that examined marijuana as a potential causative agent for automobile accidents in Colorado. The authors concluded "Alcohol remains the dominant drug associated with injury- producing traffic crashes. Marijuana is often detected, but in the absence of alcohol, it is not associated with crash responsibility."

Thank you for your consideration, drbob

Original post, 9:35 a.m. March 8: HB 1261, Representative Claire Levy's bill to establish THC driving limits, comes up for public comment on Thursday afternoon, and marijuana advocates affiliated with the Cannabis Therapy Institute are likely to show up in force to oppose it. Why? Among other reasons, the organization rejects the idea that THC can be equated to alcohol in terms of causing driving impairment and suggests that the standards set by the bill are fatally flawed.

Immediately below, find a Cannabis Therapy Institute release featuring information about the hearing and an argument against the measure provided by medical marijuana attorney Lauren Davis. Then page down to read HB 1261 in its entirety, as well as to check out CTI's "Action Alert" about the bill.

Cannabis Therapy Institute release:

THC/DUI Bill Hearing on Thursday (3/10)

House Judiciary Committee Hearing on HB 1261 DATE: Thurs., March 10, 2011 LOCATION: Hearing Room 0107, basement, state Capitol Building, 200 E. Colfax, Denver, CO (Note, this room only seats about 40 people so arrive early. There are 3 other bills on the agenda before the DUI bill.) TIME: 1:30pm

Capitol Bill Room (for last minute changes): (303) 866-3055

Attire: Dress to Impress Provisions: Bring food and water, as the hearing may last a while.

Sign up on CTI's email list for updates: http://www.CannabisTherapyInstitute.com

LISTEN LIVE ONLINE You listen online to the House Judiciary ommittee hearing: http://www.coloradochannel.net/

BACKGROUND HB1261 would declare that anyone found driving with 5 nanogram/milliliters or more of THC in their bloodstream would be guilty of "DUI per se" and subject to a misdemeanor offense and the possible revocation of their driver's license. Click here for more info: http://www.cannabistherapyinstitute.com/bills/dui/

FROM ATTORNEY LAUREN DAVIS: On Thursday, March 10, the House Judiciary Committee will hold a Hearing on HB 11-1261, the DUI/THC bill. Rep. Claire Levy has sponsored a bill that will set a per se 5 ng/mL limit on THC in the bloodstream. This means that if you get pulled over and are suspected of driving under the influence, if blood or urine tests show your THC levels are above 5 ng, you essentially will have NO defense to the charge of driving while impaired. The DA will not have to show your driving was poor or impaired to "even the slightest degree." The law will put the burden on you to overcome that presumption -- a battle you will lose.

This bill is EXTREMELY problematic for many practical reasons. There is NO research showing that 5 ng/ML of THC corresponds to any impairment in drivers (unlike with alcohol BAC, where numerous studies have shown that drivers demonstrate impairment at .05.) In fact, most studies have not been able to show any correlation between THC and driving impairment, even at significantly higher levels of THC ingestion.

Moreover, some jurisdictions contract with private labs to test your THC levels, and these labs consistently over-report and incorrectly report THC levels. The criminal defense bar has tried to remedy this with no avail. Under this bill, these labs will be inundated with testing and will likely provide even less accurate results. I have a client who spent tens of thousands of dollars to defend himself against an erroneous DUID charge -- the labs results were GROSSLY in error. After spending thousands of dollars paying a private lab to re-test the THC levels, we proved he had no THC in his blood. Can you afford to do spend that?

Please show up to speak against this bill. Being convicted of a DUID (driving under the influence of drugs) will have HORRIBLE life-long and life-altering consequences for you. Not only will you automatically lose your driver's license for up to a year, you will be subject to higher insurance premiums for life; you also could lose your health insurance, your professional license, your job, not be able to travel to many foreign countries (including Canada) and much more.

And, most importantly, in many jurisdictions in CO, you will no longer be able to use your physician recommended medical marijuana once you are convicted. No matter what your medical need, a Judge will have the authority to tell you you cannot medicate with THC. And despite multiple attorneys' attempts to appeal this issue to a higher court, the Court of Appeals refuses to review this probation requirement.

It is essential that we get the legislature to VOTE NO on this bill. Please pull out all stops to make your voice heard.

Lauren C. Davis Attorney At Law 600 17th St., Suite 2800 Denver, CO 80202 303-634-2268

Page down to read HB 1261 and see a Cannabis Therapy Institute "Action Alert" about the bill.

HB 1261:

Medical Marijuana Patients May Lose Driving Privileges

ACTION ALERT: Stop HB 11-1261, the THC/DUI Bill

In the third major attack on medical marijuana patient rights in Colorado to come out of the state legislature this year, House Bill 11-1261 was introduced on Mon., Feb. 14, 2011. This bill would declare that anyone found driving with 5 nanogram/milliliters or more of THC in their bloodstream would be guilty of "DUI per se" and subject to a misdemeanor offense and the possible revocation of their driver's license. You can read the full bill on the state's website: http://www.leg.state.co.us/

The bill was introduced by Rep. Claire Levy (D-Boulder) and Rep. Mark Waller (R-El Paso County), both members of the House Judiciary Committee. The bill was introduced by Rep. Levy, an attorney, in order to curb an imaginary crisis of "stoned drivers" in Colorado. Despite repeated requests from CTI, Rep. Levy has failed to point to one case where marijuana was the sole cause of any traffic accident.

Research shows that there is no correlation between THC blood levels and impairment. The National Highway Traffic Safety Administration released a study in 2004 which shows that chronic cannabis users, such as medical marijuana patients, normally average a much higher concentration of THC in their bloodstream than 5 ng/mL AND that this does not necessarily cause impairment. http://www.nhtsa.gov/people/injury/research/job185drugs/cannabis.htm

Dr. Robert J. Meladmede, a University of Colorado biology professor and CEO of Colorado Springs-based Cannabis Science, says the Rep. Levy's thinking on this is backwards. He stated that casual users will have often have lower levels than 5 ng/mL and may actually be impaired, while frequent users will have higher levels in their bloodstream, yet not be impaired. Click here to read Dr. Bob's full letter and research : http://www.cannabistherapyinstitute.com/bills/dui/drbob.let.html

Rep. Levy states that currently there is no nanogram limit on THC and that currently any amount of THC is enough to prove impairment. She believes that setting a limit will make the law more objective. However, in the absence of any problem, this will only make it easier for courts to convict patients of impaired driving, whether they were actually impaired or not. Instead of setting an arbitrary limit on THC in the bloodstream, more research needs to be done on better roadside impairment tests and training, to help determine whether people are impaired from any cause. There is no nanogram limit for oxycontin or other drugs that may impair drivers. Medical marijuana patients are once again treated like second-class citizens for their choice of medicine. Rep. Levy wants to force cannabis patients back onto their prescription medications, which are not routinely tested for by law enforcement.

This bill will also force anyone suspected of driving under the influence of THC to give their blood to the government. Currently, a suspected impaired driver has the choice of a urine test or a blood test. Since the nanogram limits can only be tested for in the blood, patients will be subjected to an involuntary extraction of their blood if they are ever stopped by the police.

The Department of Revenue stated last year that they intended to issue their new medical marijuana patient ID cards through the Colorado Department of Motor Vehicles. Will patients now be asked to surrender their driver's licenses when they apply for a medical marijuana card?

This is another example of the state requiring you to surrender your Constitutional rights to cannabis medicine in exchange for the "privilege" of driving.


This is the third bill introduced in the state legislature this year attacking the rights of patients (HB1243, the Patient Rights Elimination "Cleanup Bill", HB1250, the Medical Marijuana Edible Products Ban, and HB1261, the Medical Marijuana DUI Bill). All have been assigned to the House Judiciary Committee. If you haven't written them yet on these bills, please do so now. See below.

DONATIONS REQUESTED The medical marijuana industry gave $10 million to the state in application fees last year. That money is now being used to eliminate the industry, destroy patient rights, and put MMC's out of business. CTI is committed to fighting industry over-regulation and preserving patient rights. If you are an MMC-applicant, please become a CTI sponsor and become a partner in the fight to protect patient rights and your business livelihood. If you are a patient, please ask your MMC-applicant to support CTI. WE NEED YOUR HELP -- Please be generous. http://www.cannabistherapyinstitute.com/donate.html


Sample letter to House Judiciary Committee

Please vote no on HB1261 and do more research on the bill to set a nanogram limit on cannabis. There is no evidence showing a link between THC blood concentration and impairment. Other drugs that impair people, like oxycontin, do not have nanogram limits. This bill is unfair to medical marijuana patients and will force patients back on prescription medications that do not have nanogram levels and are not routinely tested for by the police. Please at least include an exemption for medical marijuan patients.

COPY AND PASTE EMAILS: bob.gardner.house@state.co.us, mark.barker.house@state.co.us, brian@briandelgrosso.com, crisanta.duran.house@state.co.us,repkagan@gmail.com, pete.lee.house@state.co.us, claire.levy.house@state.co.us, rep.nikkel@gmail.com, su.ryden.house@state.co.us, jerry.sonnenberg.house@state.co.us, mark.waller.house@state.co.us, info@cannabistherapyinstitute.com

Please send CTI copies of any letters you send: info@cannabistherapyinstitute.com

Contact your local Reps too: http://www.leg.state.co.us/

House Judiciary Committee Members Phone and Email

BOB GARDNER, Chair Colorado State Representative, District 21 Capitol Phone: (303)866-2191 E-Mail: bob.gardner.house@state.co.us

MARK BARKER, Vice Chair Colorado State Representative, District 17 Capitol Phone: 303-866-3069 E-Mail: mark.barker.house@state.co.us

BRIAN DELGROSSO Colorado State Representative, District 51 Capitol Phone: (303)866-2947 E-Mail: brian@briandelgrosso.com

CRISANTA DURAN Colorado State Representative, District 5 Capitol Phone: 303-866-2925 E-Mail: crisanta.duran.house@state.co.us

DANIEL KAGAN Colorado State Representative, District 3 Capitol Phone: (303)866-2921 E-Mail: repkagan@gmail.com

PETE LEE Colorado State Representative, District 18 Capitol Phone: 303-866-2932 E-Mail: pete.lee.house@state.co.us

CLAIRE LEVY -- SPONSOR Minority Whip Colorado State Representative, District 13 Capitol Phone: (303)866-2578 E-Mail: claire.levy.house@state.co.us

B.J. NIKKEL Majority Whip Colorado State Representative, District 49 Phone: 303-866-2907 E-mail: rep.nikkel@gmail.com

SU RYDEN Asssistant Minority Caucus Chair Colorado State Representative, District 36 Capitol Phone: 303-866-2942 E-mail: su.ryden.house@state.co.us

JERRY SONNENBERG Colorado State Representative, District 65 Capitol Phone: 303-866-3706 Email: jerry.sonnenberg.house@state.co.us

MARK WALLER -- SPONSOR Assistant Majority Leader Colorado State Representative, District 15 Capitol Phone: (303)866-5525 E-Mail: mark.waller.house@state.co.us

More from our Marijuana archive: "Medical marijuana: Video of rep shredding MMJ amendment shows no spitting by advocate."

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