Odor of Marijuana and DUI in Arizona: Why Smell Alone Isn’t Enough for Probable Cause
With marijuana now legal for both recreational and medical use in Arizona, understanding how these changes affect DUI (Driving Under the Influence) investigations is crucial. A common point of confusion for drivers and even law enforcement officers is whether the mere odor of marijuana provides sufficient justification for a DUI arrest. While marijuana impairment is illegal, the issue of determining probable cause is far more complex than many realize.
This blog post will explore the distinction between reasonable suspicion and probable cause in the context of DUI investigations and dive into key Arizona cases that have shaped the law on this topic. We’ll cover why the smell of marijuana, without more, isn’t enough to justify a DUI arrest and what protections the courts have established for Arizona drivers.
Reasonable Suspicion vs. Probable Cause: A Quick Refresher
To appreciate the legal landscape, it’s essential to distinguish between two fundamental concepts:
Reasonable Articulable Suspicion:
This standard is the threshold for initiating a traffic stop or conducting a brief detention. Officers must have specific, objective facts to suspect a driver may be engaged in unlawful activity. This is a lower bar than probable cause.Probable Cause:
Required for making an arrest or conducting a warrantless search, probable cause means there is enough evidence for a reasonable person to believe a crime has occurred. It is a higher standard that demands more than mere suspicion.
In the context of DUI cases, an officer might stop you for a traffic violation based on reasonable suspicion. However, to make a DUI arrest, the officer must have probable cause to believe you are impaired to the slightest degree.
Arizona Law on the Odor of Marijuana
Arizona law explicitly addresses how the odor of marijuana fits into investigations. A.R.S. § 36-2852(C) states that the odor of marijuana or burnt marijuana, by itself, does not constitute reasonable articulable suspicion of a crime, except in the context of a DUI investigation under A.R.S. § 28-1381. Even in DUI cases, the odor of marijuana alone does not automatically provide probable cause for arrest. The smell can be one factor in the overall evaluation, but courts require corroborating evidence of impairment.
Key Court Cases Clarifying Probable Cause for Marijuana DUIs
1. Kirsten v. Arizona Department of Transportation
In Kirsten v. ADOT, the court ruled that the presence of marijuana metabolites in a driver’s blood is insufficient to justify penalizing the driver without additional evidence of impairment. This case highlights the fact that THC metabolites can remain in a person’s system long after the psychoactive effects of marijuana have worn off. Therefore, a positive blood test alone does not prove that a driver was impaired at the time of the traffic stop.
This case is significant because it establishes that:
Non-impairing metabolites cannot be used as definitive proof of impairment.
DUI charges require clear evidence linking marijuana consumption to actual impairment while driving.
In other words, merely detecting the presence of marijuana in a driver’s system is not enough to support a DUI conviction.
2. Darrah v. McClennen
In Darrah v. McClennen, the Arizona Court of Appeals ruled that medical marijuana users can be prosecuted for DUI, but the prosecution must still prove impairment. The fact that a driver is a registered medical marijuana user does not exempt them from DUI laws, but neither does it automatically make them guilty of DUI.
This case reinforces that:
Medical marijuana use is legal, but driving while impaired by marijuana is not.
The state has the burden to prove actual impairment, not just marijuana consumption.
For defendants, this means that a DUI arrest cannot be justified solely on their admission of medical marijuana use or the odor of marijuana. There must be evidence of how the marijuana use impacted their ability to drive safely.
3. State v. Cheatham
In State v. Cheatham, the Arizona Supreme Court upheld that the odor of burnt marijuana can provide probable cause for a vehicle search, but the case stops short of saying that the odor alone justifies a DUI arrest. In this case, the officer smelled burnt marijuana during a traffic stop for a window tint violation and searched the vehicle, finding marijuana.
Key takeaways from Cheatham include:
The odor of marijuana can justify a search of a vehicle but is not, on its own, conclusive evidence of impairment.
Probable cause for DUI requires evidence beyond what’s necessary for a vehicle search.
While a search might be justified, making the leap to arresting someone for DUI based solely on odor is legally problematic without clear signs of impairment.
4. State v. Sisco
In State v. Sisco, the Arizona Supreme Court ruled that the odor or sight of marijuana can establish probable causefor a search unless there are facts indicating lawful use under the Arizona Medical Marijuana Act (AMMA). However, this case, like Cheatham, deals with searches rather than DUI arrests.
State v. Sisco emphasizes a totality of circumstances approach:
The smell or sight of marijuana must be considered alongside other factors.
Lawful use under AMMA must be factored into the probable cause analysis.
This case highlights that while the odor of marijuana can be part of an officer’s suspicion, it cannot serve as the sole basis for determining impairment in DUI cases.
Why These Cases Matter in DUI Investigations
The cases discussed illustrate an important legal principle: in Arizona, the odor of marijuana, red eyes, or the presence of metabolites cannot be the sole basis for a DUI arrest. DUI laws focus on impairment, not just consumption. Courts have consistently required:
Clear evidence of impaired driving, such as erratic driving patterns or dangerous behavior.
Reliable Field Sobriety Tests (FSTs) that are properly administered.
Drug Recognition Evaluations (DREs) when available, to assess impairment accurately.
If law enforcement relies solely on the odor of marijuana or a driver’s admission of marijuana use, this may not withstand legal scrutiny. The Fourth Amendment protects individuals from unreasonable searches and seizures, and DUI arrests must meet the probable cause standard to be lawful.
Protecting Your Rights in a Marijuana-Related DUI Stop
If you are stopped for suspicion of a marijuana-related DUI, remember these key rights:
Right to Remain Silent: You are not required to answer questions about marijuana use.
Decline FSTs: Field Sobriety Tests are voluntary, and poor performance can be influenced by factors unrelated to impairment.
Request an Attorney: Always ask to speak with a DUI attorney before answering questions or consenting to tests.
An experienced attorney can review the evidence to ensure your rights were not violated and that the arrest was supported by probable cause.
Conclusion
In Arizona, the odor of marijuana alone is insufficient to justify a DUI arrest. Courts have repeatedly emphasized that probable cause for a DUI requires evidence of impairment, not just evidence of marijuana use. The cases of Kirsten, Darrah, Cheatham, and Sisco illustrate that DUI investigations must consider the totality of the circumstances, protecting drivers from unjust arrests based solely on smell or metabolites.
If you are facing a marijuana-related DUI charge, understanding your rights and having competent legal representation can make all the difference.
Need Help with a DUI Case in Arizona?
Contact Amanda Bynum, Tucson Criminal Defense Attorney. With experience in DUI defense and a commitment to protecting your rights, I am here to guide you through every step of the process.
