In May, 2016, Pennsylvania joined a growing list of states that have approved medical cannabis as a treatment option. Each state that has legalized medical cannabis has crafted its own set of laws and regulations with some states, like California, being lightly regulated and others, such as Pennsylvania, being more highly regulated.
This polyglot of state law is also seen in how each state enforces Driving Under the Influence laws. Essentially, it boils down to whether a state enforces “metabolite only” DUI for cannabis or whether the state law requires an actual showing of impairment. In this second scenario metabolites could be evidence of impairment, but would not, by themselves, be sufficient to charge a patient with DUI.
In Pennsylvania under current DUI law ANY level of THC metabolites is sufficient to sustain a conviction for Driving Under the Influence of a Controlled Substance. The Commonwealth is not required to prove actual impairment. For a frequent user such as a medical cannabis patient THC will be detectable for weeks if not months post-usage. Under Pennsylvania’s “implied consent” law a patient will face a driver’s license suspension if he or she refused a police officer’s request for a chemical test (even if the officer lacks evidence that the patient was actually impaired.)
Delta 9 Tetrahydrocannabinol (THC) metabolizes very quickly when ingested via oral inhalation. Shortly after ingestion THC converts to the psychoactive metabolite 11-OH-THC (Hydroxy THC). Within hours of ingestion Hydroxy THC converts to the non-psychoactive metabolite THC-COOH (Carboxy THC). This metabolite is detectable for weeks or even months after cessation of use. Unless the driver is tested shortly after consumption chemical tests are unlikely to detect actual THC or Hydroxy THC metabolites and will more than likely only detect Carboxy THC metabolites.
In other words, a medical cannabis patient under the current law would be DUI at all times. This cannot be the result our Legislature intended.
This issue has not yet been litigated in Pennsylvania, but it was addressed in 2014 by the Supreme Court of Arizona, a medical cannabis state, in the matter of Arizona v., Harris. In Harris the Supreme Court was asked to determine whether Arizona’s DUI law which prohibited operating under the influence of THC metabolites included the non-psychoactive metabolite Carboxy THC. The record in Harris demonstrated that Arizona only tested for Carboxy THC because it was detectable in the blood for days and after weeks whereas Hydroxy THC becomes undetectable within a few hours of ingestion in most case. Part of the Court’s analysis focused on the fact that an Arizona patient who legally obtained and consumed medical cannabis could be convicted of a DUI despite there being no evidence of actual impairment.
Additionally, this interpretation would criminalize otherwise legal conduct. In 2010, Arizona voters passed the Arizona Medical Marijuana Act (“AMMA”), legalizing marijuana for medicinal purposes. A.R.S. § 36-2801 et seq. Despite the legality of such use, and because § 28-1381(A)(3) does not require the State to prove that the marijuana was illegally ingested, prosecutors can charge legal users under the (A)(3) provision. Because Carboxy-THC can remain in the body for as many as twenty-eight to thirty days after ingestion, the State’s position suggests that a medical-marijuana user could face prosecution for driving any time nearly a month after they had legally ingested marijuana. Such a prohibition would apply even when the driver had no impairing substance in his or her body and notwithstanding the State’s ability to test both for THC, the primary substance that causes impairment, and Hydroxy-THC, the metabolite capable of causing impairment.
The Court concluded that because Carboxy THC was the only metabolite found the DUI conviction must be overturned.
Harris is not binding on PA Courts, but it gives guidance as to how an appellate court in Pennsylvania may treat the issue if presented with an evidentiary record that consists of a Carboxy THC only DUI conviction with no showing of actual impairment.
If you or a friend or family member is a registered patient and charged with a cannabis DUI please do not hesitate to contact us for a free and confidential consultation.