                              IN THE

   SUPREME COURT OF THE STATE OF ARIZONA
                        KRISTINA R. DOBSON,
                             Petitioner,

                                 v.

THE HONORABLE CRANE MCCLENNEN, JUDGE OF THE SUPERIOR COURT OF THE
       STATE OF ARIZONA, IN AND FOR THE COUNTY OF MARICOPA,
                          Respondent Judge,

                 CITY OF MESA PROSECUTOR’S OFFICE,
                        Real Party in Interest.


                      MARVELLE D. ANDERSON,
                            Petitioner,

                                 v.

THE HONORABLE CRANE MCCLENNEN, JUDGE OF THE SUPERIOR COURT OF THE
       STATE OF ARIZONA, IN AND FOR THE COUNTY OF MARICOPA,
                          Respondent Judge,

                 CITY OF MESA PROSECUTOR’S OFFICE,
                        Real Party in Interest.

                         No. CV-14-0313-PR
                      Filed November 20, 2015


         Appeal from the Superior Court in Maricopa County
             The Honorable Crane McClennen, Judge
              No. LC2014-000196 and LC2014-000266
                            AFFIRMED

            Opinion of the Court of Appeals, Division One
               236 Ariz. 203, 337 P.3d 568 (App. 2014)
                             VACATED
           DOBSON V. MCCLENNEN (MESA PROSECUTOR)
                      Opinion of the Court

COUNSEL:

John P. Tatz (argued), John P. Tatz Attorney at Law, P.C., Glendale,
Attorney for Kristina R. Dobson and Marvelle D. Anderson

W. Craig Jones (argued), Chief Assistant City Prosecutor, Mesa City
Prosecutor’s Office, Mesa, Attorneys for City of Mesa Prosecutor’s Office

David J. Euchner (argued), Tucson, Attorney for Amicus Curiae Arizona
Attorneys for Criminal Justice

Thomas W. Dean, Phoenix, Attorney for Amicus Curiae National
Organization for the Reform of Marijuana Laws

CHIEF JUSTICE BALES authored the opinion of the Court, in which VICE
CHIEF JUSTICE PELANDER and JUSTICES BRUTINEL, TIMMER, and
BERCH (RETIRED) joined.

CHIEF JUSTICE BALES, opinion of the Court:

¶1            The Arizona Medical Marijuana Act (“AMMA”), passed by
voters in 2010 and codified as A.R.S. §§ 36-2801-2819, allows a person who
has been diagnosed by a physician as having a debilitating medical
condition to apply for a card identifying the holder as a registered
qualifying patient. Such patients may possess and use limited amounts of
marijuana for medical reasons. The AMMA broadly immunizes them from
prosecution for using medical marijuana consistent with the Act.

¶2            Arizona’s laws generally make it a crime for a person to drive
with any amount of certain drugs, including marijuana or its impairing
metabolite, in the person’s body. A.R.S. § 28-1381(A)(3); State ex rel.
Montgomery v. Harris (Shilgevorkyan), 234 Ariz. 343, 347 ¶ 24, 322 P.3d 160,
164 (2014). We today hold that the AMMA does not immunize a medical
marijuana cardholder from prosecution under § 28-1381(A)(3), but instead
affords an affirmative defense if the cardholder shows that the marijuana
or its metabolite was in a concentration insufficient to cause impairment.




                                     2
           DOBSON V. MCCLENNEN (MESA PROSECUTOR)
                      Opinion of the Court

                                      I.

¶3           Kristina Dobson and Marvelle Anderson (“Petitioners”) were
each charged with two counts of driving under the influence (“DUI”).
Count one alleged a violation of A.R.S. § 28-1381(A)(1), which prohibits a
person from driving a vehicle in Arizona “[w]hile under the influence of …
any drug … if the person is impaired to the slightest degree.” Count two
alleged a violation of § 28-1381(A)(3), which prohibits driving a vehicle
“[w]hile there is any drug defined in § 13-3401 or its metabolite in the
person’s body.” Cannabis (marijuana) is a drug defined in A.R.S. § 13-
3401(4). Blood tests showed that each Petitioner had marijuana and its
impairing metabolite in her body.

¶4            The municipal court denied Dobson’s motion to present
evidence at trial that she held an Oregon-issued medical marijuana card
and granted the State’s motion in limine to preclude evidence that
Anderson held an Arizona-issued medical marijuana card. Neither
Petitioner sought to introduce any evidence other than their respective
medical marijuana cards. The State dismissed the (A)(1) charges and
Petitioners, after submitting the issue of guilt to the court based on a
stipulated record, were each convicted of the (A)(3) charge.

¶5            Petitioners timely appealed to the Maricopa County Superior
Court, which affirmed their convictions. They then sought special action
review in the court of appeals, which accepted jurisdiction but denied relief.
Dobson v. McClennen, 236 Ariz. 203, 205 ¶ 1, 337 P.3d 568, 570 (App. 2014).
The court of appeals held that “neither A.R.S. § 36-2811(B) nor § 36-2802(D)
provides immunity for defendants facing charges for driving with an
impermissible drug or impairing metabolite in their bodies under A.R.S.
§ 28-1381(A)(3).” 263 Ariz. at 209 ¶ 20, 337 P.3d at 574.

¶6            We granted review because whether the AMMA immunizes
a medical marijuana cardholder from DUI prosecution under § 28-
1381(A)(3) presents a recurring issue of statewide importance. We have
jurisdiction under Article 6, Section 5(3) of the Arizona Constitution and
A.R.S. § 12-120.24.




                                      3
           DOBSON V. MCCLENNEN (MESA PROSECUTOR)
                      Opinion of the Court

                                     II.

¶7            We review questions of statutory interpretation de novo.
State v. Hansen, 215 Ariz. 287, 289 ¶ 6, 160 P.3d 166, 168 (2007). A reviewing
court’s “primary objective in construing statutes adopted by initiative is to
give effect to the intent of the electorate.” State v. Gomez, 212 Ariz. 55, 57
¶ 11, 127 P.3d 873, 875 (2006). “When two statutes conflict, we adopt a
construction that reconciles them whenever possible, giving force and
meaning to each.” State v. Jones, 235 Ariz. 501, 502 ¶ 6, 332 P.3d 191, 192
(2014).
                                       A.

¶8             The AMMA broadly immunizes registered qualifying
patients for their medical use of marijuana, providing:

       A registered qualifying patient . . . is not subject to arrest,
       prosecution or penalty in any manner, or denial of any right
       or privilege, including any civil penalty or disciplinary action
       by a court or occupational or professional licensing board or
       bureau: (1) For the registered qualifying patient’s medical use
       of marijuana pursuant to this chapter, if the registered
       qualifying patient does not possess more than the allowable
       amount of marijuana.

A.R.S. § 36-2811(B)(1).

¶9            This grant of immunity is not absolute. For instance, the
AMMA does not prohibit prosecution for “[o]perating, navigating or being
in actual physical control of any motor vehicle, aircraft or motorboat while
under the influence of marijuana.” A.R.S. § 36-2802(D). However, “a
registered qualifying patient shall not be considered to be under the
influence of marijuana solely because of the presence of metabolites or
components of marijuana that appear in insufficient concentration to cause
impairment.” Id.

¶10           Arizona’s DUI laws identify separate offenses for driving
while a person is under the influence of marijuana and “impaired to the
slightest degree,” A.R.S. § 28-1381(A)(1), and driving while there is
marijuana or its metabolite “in the person’s body.” § 28-1381(A)(3). An
(A)(3) violation, unlike an (A)(1) violation, does not require the state to

                                      4
            DOBSON V. MCCLENNEN (MESA PROSECUTOR)
                       Opinion of the Court

prove that the defendant was in fact impaired while driving or in control of
a vehicle. Harris, 234 Ariz. at 347 ¶ 24, 322 P.3d at 164. Instead, marijuana
users “violate (A)(3) if they are discovered with any amount of THC or an
impairing metabolite in their body.” Id.

¶11           The (A)(1) and (A)(3) offenses also differ with respect to
possible defenses. When the state charges a person with driving while
impaired by drugs in violation of (A)(1), “[i]t is not a defense . . . that the
person is or has been entitled to use drugs under the laws of this state.”
§ 28-1381(B). In contrast, a person cannot be convicted under (A)(3) for
using a drug as prescribed by a licensed medical practitioner. A.R.S. § 28-
1381(D). Subsection (D) thus provides an affirmative defense to an (A)(3)
charge.

¶12           In Harris, we held that “[d]rivers cannot be convicted of the
(A)(3) offense based merely on the presence of a non-impairing metabolite
that may reflect the prior usage of marijuana.” 234 Ariz. at 347 ¶ 24, 322
P.3d at 164. Although we observed that “a driver who tests positive for any
amount of an impairing drug is legally and irrefutably presumed to be
under the influence,” id. at 347 ¶ 22, 322 P.3d at 164, in Harris we did not
consider the scope of the subsection (D) affirmative defense. Nor did that
case involve a driver who was a qualified registered patient.

¶13           Here, we must resolve how the AMMA affects (A)(3)
prosecutions. The State argues that the AMMA, which provides that a
registered card holder cannot be considered to be under the influence of
marijuana if it is present in an “insufficient concentration to cause
impairment,” § 36-2802(D), does not affect (A)(3) prosecutions at all
because the State is not required to prove a defendant’s impairment to
establish an (A)(3) violation. Dobson and Anderson counter that the
AMMA immunizes them from an (A)(3) prosecution because they cannot
be considered to be under the influence based solely on the mere presence
of marijuana or its metabolite in their bodies. They also contend that the
affirmative defense afforded by § 28-1381(D) applies to them.

¶14          Neither position urged by the parties represents the best
reading of the statutory provisions. The State’s view effectively renders
superfluous the “shall not be considered to be under the influence” clause
in A.R.S. § 36-2802(D). This language would be unnecessary if it only
prohibited prosecution under statutes, such as § 28-1381(A)(1), that require

                                      5
           DOBSON V. MCCLENNEN (MESA PROSECUTOR)
                      Opinion of the Court

the state to prove that the defendant is in fact impaired as a result of the
presence of marijuana or its metabolite. Section 36-2802(D) is more
plausibly interpreted as applying to statutes like § 28-1381(A)(3), which, as
we noted in Harris, presume that a defendant is impaired based on the mere
presence of any amount of marijuana or its potentially impairing
metabolites in a person’s body. 234 Ariz. at 347 ¶ 22, 322 P.3d at 164.

¶15            Petitioners, however, are also not convincing in arguing that
§ 36-2802(D) immunizes registered qualifying patients from any
prosecution under § 28-1381(A)(3). Section 36-2802(D) does not say that
registered qualifying patients cannot be prosecuted for (A)(3) violations.
Instead, it provides that such patients, who use marijuana “as authorized”
by the AMMA, id. § 36-2802(E), cannot “be considered to be under the
influence of marijuana solely because of the presence of metabolites or
components of marijuana that appear in insufficient concentration to cause
impairment.” Id. § 36-2802(D) (emphasis added).

¶16           Violations of § 28-1381(A)(3) include, but are not limited to,
situations in which drivers have a non-impairing amount of certain drugs
in their bodies. This reflects that the legislature, in seeking to combat the
serious problem of impaired driving, recognized that for certain drugs it
may be difficult to identify concentrations that definitively establish
whether a defendant is impaired. Harris, 234 Ariz. at 347 ¶ 22, 322 P.3d at
164; cf. A.R.S. § 28-1381(A)(2) (proscribing driving with an alcohol
concentration of .08 or more irrespective of proof of actual impairment).
Thus, the (A)(3) offense does not require the state to prove that the
defendant is in fact impaired “to the slightest degree,” § 28-1381(A)(1), but
instead requires the state to prove that the defendant has been driving or in
control of a vehicle while any amount of the proscribed drugs or their
impairing metabolites are present “in the person’s body.” Id. 28-1381(A)(3);
Harris, 234 Ariz. at 347 ¶ 24, 322 P.3d at 164.

¶17          Section (A)(3) thus casts a net that embraces drivers who have
proscribed drugs or their impairing metabolites in their bodies but who
may or may not be impaired. By its terms, § 36-2802(D) does not shield
registered qualifying patients from prosecution under (A)(3), but instead
says they cannot be considered to be “under the influence” based solely on
concentrations of marijuana or its metabolites that are insufficient to cause
impairment. When read together, the statutory provisions suggest that the


                                     6
           DOBSON V. MCCLENNEN (MESA PROSECUTOR)
                      Opinion of the Court

AMMA gives qualifying patients a limited defense rather than a general
immunity in (A)(3) prosecutions.

¶18            We reject, however, Petitioners’ argument that qualifying
patients can rely on the defense afforded by § 28-1381(D) for the use of
prescribed drugs.      Medical marijuana used pursuant to “written
certifications” under the AMMA is not “prescribed,” see A.R.S. §§ 36-
2801(18), -2804.02(A)(1); and the § 28-1381(D) defense applies to drugs
prescribed by a different class of licensed “medical providers” than those
who may issue medical marijuana certifications. Compare A.R.S. § 28-
1381(D) (defining “medical providers” as including licensed podiatrists,
dentists, medical doctors, and osteopathic physicians) with § 36-2801(12)
(defining “physician” as including licensed medical doctors and
osteopathic, naturopathic, and homeopathic physicians).

¶19          Section 36-2802(D), rather than § 28-1381(D), defines the
affirmative defense available to a registered qualifying patient to an (A)(3)
charge. If their use of marijuana is authorized by § 36-2802(D), such
patients cannot be deemed to be under the influence – and thus cannot be
convicted under (A)(3) - based solely on concentrations of marijuana or its
metabolite insufficient to cause impairment. Possession of a registry card
creates a presumption that a qualifying patient is engaged in the use of
marijuana pursuant to the AMMA, so long as the patient does not possess
more than the permitted quantity of marijuana. A.R.S. § 36-2811(A)(1).
That presumption is subject to rebuttal as provided under § 36-2811(2).

¶20             A qualifying patient may be convicted of an (A)(3) violation
if the state proves beyond a reasonable doubt that the patient, while driving
or in control of a vehicle, had marijuana or its impairing metabolite in the
patient’s body. The patient may establish an affirmative defense to such a
charge by showing that his or her use was authorized by the AMMA -
which is subject to the rebuttable presumption under § 36-2811(2) - and that
the marijuana or its metabolite was in a concentration insufficient to cause
impairment. The patient bears the burden of proof on the latter point by a
preponderance of the evidence, as with other affirmative defenses. See
A.R.S. § 13-205 (“[A] defendant shall prove any affirmative defense raised
by a preponderance of the evidence.”).

¶21          Petitioners contend that it is inappropriate to assign to
qualifying patients the burden of showing that they did not have marijuana

                                     7
            DOBSON V. MCCLENNEN (MESA PROSECUTOR)
                       Opinion of the Court

concentrations sufficient to cause impairment because there is no
commonly accepted threshold for identifying such concentrations. Cf.
Harris, 234 Ariz. at 347 ¶ 22, 322 P.3d at 164 (noting that “there is no
generally applicable concentration that can be identified as an indicator of
impairment for illegal drugs”). This contention, however, argues in favor
of assigning the burden to patients to prove, by a preponderance, that the
marijuana concentration in their bodies while they were driving was not
sufficient to cause impairment. The risk of uncertainty in this regard should
fall on the patients, who generally know or should know if they are
impaired and can control when they drive, rather than on the members of
the public whom they encounter on our streets. Cf. Harris, 234 Ariz. at 346
¶ 20, 322 P.3d at 163 (noting state’s compelling interest in protecting public
from drivers who may be impaired by consumption of controlled
substances).
                                       B.

¶22           Petitioners made no effort to show that the marijuana in their
bodies was in an insufficient concentration to cause impairment. Instead,
they argued that the AMMA categorically barred the (A)(3) charge, and
they offered only their respective registry identification cards into evidence.
Although evidence of possession of a registry card would generally be
admissible in an (A)(3) prosecution to invoke the presumption that the
patient was using marijuana pursuant to the AMMA, it does not suffice to
establish the § 36-2802(D) affirmative defense. Any error by the trial court
in excluding evidence of the registry cards was harmless in light of the
stipulations by Petitioners that they had marijuana in their bodies while
driving (blood tests revealed both THC and its impairing metabolite
hydroxy-THC) and their failure to offer any evidence that the
concentrations were insufficient to cause impairment.

                                          III.

¶23           Rather than shielding registered qualifying patients from any
prosecution under A.R.S. § 28-1381(A)(3), the AMMA affords an
affirmative defense for those patients who can show, by a preponderance
of the evidence, that the concentration of marijuana or its impairing
metabolite in their bodies was insufficient to cause impairment. We vacate
the opinion of the court of appeals and affirm the Petitioners’ convictions.



                                      8
