In State ex rel. Montgomery v. Harris, 234 Ariz. 343, 345-46, 347,16, 24, 322 P.3d 160, 162-63, 164 (2014), the defendantwas prosecuted for DUI under 28-1381(A)(3) based on testing results indicating only the presence of an inactive marijuana metabolite. 234 Ariz. at 343,1, 322 P.3d at 160. The supreme court held that a "non-impairing" metabolite of marijuana is not a "proscribed drug" listed in A.R.S. 13-3401 and therefore its presence in a person's body cannot support a conviction for DUI pursuant to A.R.S. 28-1381(A)(3). Harris, 234 Ariz. at 347,24, 322 P.3d at 164. In reaching this conclusion, the court explained that the AMMA legalizes marijuana for medicinal purposes, but "despite the legality of such use, prosecutors can charge legal users under the (A)(3) provision" because that statute "does not require the State to prove that the marijuana was illegally ingested." Id.at 346-47,16, 322 P.3d at 163-64. Based on the statute's intent--"to prevent impaired driving"--the court thus "held that the 'metabolite' reference in 28-1381(A)(3) is limited to any of a proscribed substance's metabolites that are capable of causing impairment." Id.24.In State v. Phillips, 178 Ariz. 368, 873 P.2d 706 (App. 1994), the defendant challenged the facial validity of A.R.S. 28-692(A)(3) (1994) (now 28-1381(A)(3)), arguing it was unconstitutionally vague and overbroad. 178 Ariz. at 370, 873 P.2d at 708. The Court disagreed, noting that the legislature intended to create a "per se prohibition" and a "flat ban on driving with any proscribed drugs in one's system." Id. at 372, 873 P.2d at 710. The Court determined that the legislative ban extends to all substances, whether capable of causing impairment or not. The Court therefore concluded that the statute "precisely defines, in unequivocal terms, the type of behavior prohibited." Id. at 371, 873 P.2d at 709. The Court also rejected the defendant's equal protection argument, concluding the "legislature was reasonable in determining that there is no level of illicit drug use which can be acceptably combined with driving a vehicle." Id. at 372, 873 P.2d at 710. The Court emphasized the "compelling legitimate interest" the state has to protect the public from impaired driving because the "potential for lethal consequences is too great." Id. Based on this interpretation of the statute, we upheld the constitutionality of 28-692(A)(3). Id.