In Arizona, it is unlawful for a person to drive a vehicle (1) while under the influence of any drug, or any combination of liquor and/or drugs if the person is impaired to the slightest degree, OR (2) while there is any drug or its metabolite in the person's body. Ariz. Rev. Stat. Ann. §§ 28-1381(A)(1), (3) (West 2010). However, a registered qualifying medical use patient shall not be considered to be under the influence solely for having marijuana metabolites in his or her system.
(1) Driving under the influence of any drug
The fact that the person is or has been entitled to use a drug in this state is not a defense to this first type of DUI. Id. § 28-1381(B).
(2) Driving while there is any drug or metabolite in the person's body (per se law)
NOTE: Actual impairment is not an element of this offense. Cannabis metabolites can be detected in a person's body up to one month after use, thus it is possible to be convicted of this type of DUI weeks after a person last ingested cannabis.
A person using a drug, as prescribed by a medical practitioner is not guilty of this second type of DUI. Id. § 28-1381(D).
NOTE: A recommendation to use marijuana from a medical practitioner is not a prescription.
Arizona's interpretation of the federal Constitution allows law enforcement officials to conduct sobriety checkpoints.
Wozniak v. Galati, 30 P.3d 131 (2001) – Found that a metabolite present in defendants system could reasonably allow a jury to conclude that defendant was driving while under the influence of drug or its metabolite.
State v. Gaffney, 8 P.3d 376 (2000) – Implied consent statutory warnings were unnecessary when defendant gave express consent to a test of blood, breath, or urine.
State v. Hammonds, 192 Ariz. 528 (App. Div.1 1998) -- Statute proscribing driving with a drug metabolite in one's body is rationally related to legitimate state purpose and does not violate equal protection clause. Even though scientific evidence showed conclusively that the mere presence of a metabolite does not necessarily represent impairment, contrary expert testimony successfully showed that the presence of inert metabolites does not rule out impairment.
State v. Love, 897 P.2d 626, 629 (1995) -- Factors to be considered when determining whether defendant "operated" motor vehicle: whether the vehicle was running or the ignition was on; where the key was located; where and in what position the driver was found in the vehicle; whether the person was awake or asleep; if the vehicle's headlights were on; where the vehicle was stopped (in the road or legally parked); whether the driver had voluntarily pulled off the road; time of day and weather conditions; if the heater or air conditioner was on; whether the windows were up or down; and any explanation of the circumstances advanced by the defense.
Arizona has a zero tolerance per se drugged driving law enacted for cannabis, cannabis metabolites, and other controlled substances. (Arizona Revised Statutes, Section 28-1381)
Arizona's law calls for mandatory imprisonment of 24 hours and not more than six months upon conviction for a first offense.