Dobson v. McClennen
238 Ariz. 389
| Ariz. | 2015Background
- Arizona voters enacted the Arizona Medical Marijuana Act (AMMA), A.R.S. §§ 36-2801–2819, authorizing qualifying patients to use and possess limited marijuana and providing immunities for medical use.
- Arizona law separately criminalizes driving with any amount of certain drugs or their impairing metabolites in the body, A.R.S. § 28-1381(A)(3); driving while impaired to the slightest degree is § 28-1381(A)(1).
- Petitioners Kristina Dobson and Marvelle Anderson, both found to have THC and its impairing metabolite in blood tests after driving, were charged with two DUIs each (A)(1) and (A)(3); (A)(1) charges were dismissed and they were convicted on (A)(3).
- Trial courts excluded evidence of their medical marijuana registry cards; the superior court and court of appeals affirmed convictions; the Arizona Supreme Court granted review.
- AMMA § 36-2802(D) states registered qualifying patients shall not be considered under the influence solely because of metabolites present in insufficient concentration to cause impairment; AMMA also provides a presumption that possession of a registry card shows authorized AMMA use, subject to rebuttal.
- The core question: whether AMMA immunizes cardholders from (A)(3) prosecutions or instead supplies an affirmative defense limited to non-impairing concentrations.
Issues
| Issue | Petitioners' Argument | State's Argument | Held |
|---|---|---|---|
| Whether AMMA immunizes qualifying patients from prosecution under A.R.S. § 28-1381(A)(3) (driving with any amount of proscribed drug or metabolite) | AMMA precludes (A)(3) convictions because patients "shall not be considered to be under the influence" based solely on presence of metabolites | AMMA does not affect (A)(3); (A)(3) requires no proof of impairment, so AMMA language is irrelevant to (A)(3) prosecutions | AMMA does not categorically immunize; it provides a limited defense but does not bar prosecution under (A)(3) |
| Whether the affirmative defense in § 28-1381(D) for ‘‘prescribed’’ drugs applies to AMMA medical marijuana users | Petitioners argued AMMA patients can invoke § 28-1381(D) affirmative defense | State argued § 28-1381(D) defense covers drugs prescribed by certain medical providers, not AMMA certifications | § 28-1381(D) does not apply; AMMA § 36-2802(D) supplies the relevant affirmative defense (burden on defendant to prove non-impairing concentration) |
Key Cases Cited
- State ex rel. Montgomery v. Harris, 234 Ariz. 343, 322 P.3d 160 (Ariz. 2014) (A.R.S. § 28-1381(A)(3) allows conviction based on presence of any amount of drug or impairing metabolite; court noted lack of generally applicable concentration for impairment)
- State v. Gomez, 212 Ariz. 55, 127 P.3d 873 (Ariz. 2006) (court’s objective in construing initiative statutes is to effectuate electorate intent)
- State v. Hansen, 215 Ariz. 287, 160 P.3d 166 (Ariz. 2007) (statutory interpretation reviewed de novo)
- State v. Jones, 235 Ariz. 501, 334 P.3d 191 (Ariz. 2014) (when statutes conflict, courts reconcile them to give force and meaning to each)
Decision summary: The Court held AMMA does not grant categorical immunity from § 28-1381(A)(3) prosecutions; instead qualifying patients may raise an AMMA-based affirmative defense by proving by a preponderance that their marijuana or metabolite concentration was insufficient to cause impairment. Possession of a registry card creates a rebuttable presumption of authorized AMMA use, but defendants bear the burden to show non-impairing concentration.