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Cruising the Highway: How to Avoid Getting Arrested and Convicted of a THC DUI – Part 2

Last month in “Part 1” of this series on cannabis DUIs, I gave a general overview of Arizona’s DUI law as it pertains to cannabis and some basic tips on how to avoid having the police sniffing around your car (literally) during a traffic stop. This month I’m going into a little bit more detail about how to handle a traffic stop that ends up going sideways and turning into a DUI investigation. Aside from having cannabis or paraphernalia in your car in plain view, this usually only happens when a cop detects the odor of marijuana. To prevent this from happening, it’s a good idea not to have cannabis in your car in the first place, but if you must, then keep it in the trunk or at least in an odor proof container.

I won’t go into more detail about the whole odor issue here as that is a future article in and of itself. If you get pulled over and the cop asks you if you have any marijuana in the car, then he probably smells it. If he asks you when you last smoked marijuana, then he probably smells it. For now, suffice it to say that if a cop pulls you over and says he smells marijuana and you want to avoid a search of your car, you need to speak up and tell him that you are a patient and offer to show him your card. Otherwise, the officer can go ahead and search your car. Okay, now let’s talk about how to handle the situation if the officer starts to suspect that you are impaired.

If the officer asks you when you last smoked, then you know she is thinking that you might have recently smoked. You can choose to remain silent and ask to talk to a lawyer, but that won’t do much to alleviate her suspicion. If it has been more than 24 hours since you last smoked, then you might want to tell her that, because cops and prosecutors are under the impression that cannabis can cause impairment for up to 24 hours. Specifically, they rely on an old study from the 50s that was done using pilots in flight simulators in support of their claim that a person’s capacity for “divided attention” is impaired 24 hours later. Thus, if you smoked more recently than 24 hours ago, then it’s best to invoke your right to remain silent. That may make the cop more suspicious, but she can’t use the fact that you invoked your 5th Amendment rights as part of her probable cause calculation. Whatever you do, do not tell her that you consumed an edible in the last 24 hours because the impairing effects of cannabis in its edible form last much longer. Incidentally, the study about divided attention being affected for up to 24 hours was a very poor study and conflicts with every other more recent study which finds that the impairing effects of cannabis dissipate in about 2 hours.

In any event, let’s suppose that the officer thinks that he has a reasonable suspicion that you are impaired, for whatever reason. His next move will be to ask you to perform standardized field sobriety tests (SFSTs). These tests are usually the centerpiece of a cop’s probable cause. The problem with SFSTs is that, although the interpretation of a driver’s performance is highly subjective, a trained officer’s interpretation is given a lot of weight by judges and juries. SFSTs include things such as walking a straight line, touching the tips of your fingers to the tip of your nose, standing on one leg while counting 30 seconds, etc. They also include the Horizontal Gaze Nystagmus (HGN) which is where the cop waves a pen around in front of your face and tells you to follow it with your eyes without moving your head. Interestingly, cops will testify that cannabis use does not cause nystagmus. They claim, however, that other observations of the eyes, such as dilated pupils or “rebound dilation” are indicators of cannabis use. Checking for “rebound dilation” is not a standardized test, nor are a slew of other anecdotal tests, including checking the driver for an elevated pulse rate, eyelid tremors, a green tongue and raised taste buds. All these observations were made up by police and are used to obtain probable cause to justify an arrest. A smart driver will not agree to submit to any of them. Instead, politely and respectfully decline to consent.

But what if you do end up getting arrested for DUI? Sometimes the police will ask you to take more field sobriety tests at the station. You should refuse again. Never, at any point, is there a penalty for refusing to do any of the tests discussed so far (i.e., field sobriety and anecdotal tests), although the state can use your refusal as evidence that you knew that you were impaired. Inevitably, however, the arresting officer will likely ask you to consent to a test of your bodily fluids, either your breath, urine or blood. Only a blood test can detect THC and its active metabolite, hydroxy THC. Therefore, if they suspect cannabis impairment, then the blood test is what they will ask you to do. Unlike the advice I have given to always refuse field sobriety and anecdotal tests, my advice is that you always agree to a bodily fluid test if requested.

But you may be thinking, if I refuse the blood test, at least they can’t prove that I had THC in my system, right? Wrong. Arizona allows the police to obtain search warrants over the phone and every jurisdiction has judges on call 24/7 who are happy to answer the phone in the middle of the night, if necessary. This means that despite your refusal, they will get your blood no matter what, by force if necessary. I recently had a client who refused and was held down by multiple officers as she screamed for help. The whole thing was deemed perfectly lawful because they did not use excessive force. If you refuse a breath, urine or blood test, not only will you be forced to submit anyway despite your refusal, you also will automatically be penalized with a one-year license suspension. Alternatively, if you submit to the test and it is positive, then your license is suspended for only 90 days. In summary, if you are arrested, decline to perform SFSTs, but agree to take a breath, urine or blood test if requested.

Next: what if they arrest you, get your blood, and the results come back showing active THC metabolites and you get charged with DUI? Is all hope lost? Far from it! Next month, in the third and final installment of this series, I will tell you how you can beat a cannabis DUI at trial. Until then, implement the suggestions in the last two installments, and with any luck you will never have to worry about being charged with a cannabis DUI in the first place.


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