Defendant charged with marijuana DUI asserted a medical marijuana affirmative defense in the jury trial, but was erroneously precluded from submitting the medical marijuana card as evidence of his authorized use.
The defendant was stopped by police and charged with driving under the influence (DUI). The arresting officer testified that the driver drifted into the other lane, corrected, and was then pulled over. The officer smelled marijuana and observed driver’s bloodshot eyes. When asked by police, defendant said he smoked marijuana upon awakening that morning. Defendant performed field sobriety tests and was observed experiencing body tremors and eye tremors. A blood sample showed a concentration of 26.9 ng/ml of marijuana metabolite THC.
Defendant was charged with DUI in violation of ARS § 28-1381(A)(1) for driving impaired to the slightest degree; and charged with DUI in violation of ARS § 28-28-1381(A)(3) for driving with marijuana or marijuana metabolite in his body capable of causing impairment.
The defendant offered an affirmative defense at trial. First, he was authorized by the Arizona Medical Marijuana Act (AMMA) to use medical marijuana and, second, that the concentration of marijuana or it’s metabolite in his body was insufficient to cause impairment. See ARS § 36-2802(D).
In asserting this affirmative defense, a defendant carries the burden of proof beyond a preponderance of the evidence. This defendant sought to offer his medical marijuana card (MJ card) into evidence to support the premise of his affirmative defense.
Reasoning that it was irrelevant to the DUI charges, the Mesa Municipal Court granted prosecutor’s pre-trial motion to preclude evidence of defendant’s MJ card. Defendant objected on the basis that keeping out evidence of his MJ card would mislead the jury into believing it was illegal for him to ingest marijuana when that was not so. Expert witnesses testified as to the amount of THC concentration in the blood might be impairing, yet no scientific consensus was reached.
In a trial by jury, the defendant was acquitted of the (A)(1) DUI charge and convicted of the (A)(3) DUI charge. He was sentenced to 180 days in jail with half suspended. The defendant appealed his conviction to the Superior Court in Maricopa County.
Meanwhile, the Arizona Supreme Court decided Dobson v. McClennen, 238 Ariz. 389, 361 P3d 374 (2015), before defendant’s appeal to the Superior Court. In light of Dobson, the Superior Court concluded that, even though the Mesa Municipal Court erred in precluding MJ card evidence, the error was harmless. The defendant was not prejudiced because he was unable to obtain an expert to testify that he would not have been impaired at 26.9 ng/ml.
The Court of Appeals accepted special action jurisdiction and, granting relief to the defendant, vacated the (A)(3) DUI conviction and remanded the case to the municipal court for further proceedings.
After Dobson, the AMMA applies to an (A)(3) DUI, offering limited immunity from prosecution. The MJ card-holder cannot possess more than the allowable amount of marijuana. The MJ card-holder cannot be considered under the influence of marijuana solely because he has marijuana metabolites or components of marijuana in his body when concentration is insufficient to cause impairment. Furthermore, the concentration that impairs one driver will not necessarily impair another.
♦ The Dobson affirmative defense is applicable to the (A)(3) DUI if any marijuana or marijuana metabolite was in the driver’s body.
♦ The Dobson affirmative defense requires defendant provide proof that he was not actually impaired – that is, the effect of marijuana or marijuana metabolite in his body was not impairing. He is not required to show proof that the THC concentration in his body could not impair any human being or hypothetical driver in the abstract.
♦ Dobson would assign the burden on the MJ card-holder who should know if he is impaired and can control a vehicle when driving.
♦ To assert the Dobson affirmative defense, defendant is not required to present expert testimony on the issue of THC impairment of the driver.
♦ Nothing precludes the defendant from offering non-expert witness testimony on the question of marijuana impairment.
♦ Nothing precludes the MJ card-holder’s own testimony for the purpose of establishing the affirmative defense.
♦ Unlike alcohol, there is no marijuana presumptive impairment limit established by law.
♦ There is no scientific consensus on what concentration of marijuana or marijuana metabolite is generally sufficient to impair a human being.
In Judge Howe’s dissenting opinion, the majority blurred the lines of the (A)(1) DUI and (A)(3) DUI offenses. The dissent agreed the trial court erred in precluding evidence of the MJ card, but that this defendant was not prejudiced by such harmless error.
For precise language, read the court’s original opinion. Legal citations omitted.
To learn more about DUI in Arizona criminal law, read this overview of driving under the influence.