What Percentage of DUIs Are Drug-Related?

Interviewer: We’ll focus on illegal drug-related DUIs for illegal first. Percentage wise, out of all the DUIs you see, what percentage tend to be for illegal drugs like marijuana, cocaine, or heroin?

Brian: As far as DUIs, generally speaking, illegal drugs probably represent about 10% of the total cases. I would say of the DUIs concerning illegal drugs and prescription medications, illegal drugs are probably about 40% of the total.

Prescription Drug Use While Driving Comprise Most of the DUI Cases

Interviewer: It’s actually more prescription drugs that cause DUIs, is that right?

Brian: We definitely see more prescription drug cases. The police are starting to really arrest people that have been taking medications for their entire lives, people who are on new medications and people who had their medication doses changed.

The problem is the prosecutors have to prove that it was the medications that caused impairment. So if there is any issue with driving, any type of weaving, any type of swerving, any wide turn, anything, the prosecutor will blame that on the prescription medication simply because the prescription medications were present.

How Do the Police Suspect Impairment By Prescription Medication?

Interviewer: In those prescription medication cases, when people are stopped by Police, how does it end up with the police suspecting they are on prescription medications? Do they just ask or are people truly impaired by the drugs?

Brian: A lot of prescription medications cases don’t start out with the belief that someone is impaired by the prescription medications. Often an officer will see something they think is odd.

Sometimes, it is bloodshot, watery eyes. Sometimes it is slurred speech. Sometimes it is dilated pupils or overly large pupils. An officer will sometimes just rule out alcohol impairment but feel that there is some sort of other impairment present.

Blood Tests Are the Most Common Method for Testing for the Presence of Prescription Drugs

Quite often what happens is an officer will believe that there is alcohol impairment and draw blood under the theory that there is alcohol impairment. When the results come back, thy show a very low presence of alcohol or no presence of alcohol.

The police will simply test the blood for prescription medications or drugs at that point in a ‘Hail Mary’ move to see if there is anything present. If there is something present, such as prescription medications, it is sometimes the same prescription medications that people have been taking for years.

The prosecutor will then allege that it was those prescription medications that must have caused the impairment because impairment was observed.

If You Are Stopped, Should You Tell a Police Officer that You Are Taking Prescription Medication?

Interviewer: Does it help anyone to tell the police that they are on certain prescription medications or does it just hurt their case?

Brian: I think it does hurt the case. With prescription medications, there are some that might cause impairment, and there are others that absolutely would not cause impairment.

Admitting that you were taking prescription medication is on par with admitting that you only had two drinks or that you only smoked a ”little” marijuana.

Admission is going to be used against you and it gives the prosecutor ammunition to say, “See these people were on medication, there is no denying they are on medication, that must have been what the officer was seeing that indicated that there was some sort of impairment present at the time.”

Interviewer: I’m sure most people don’t even think or dream that taking prescription medication could end up with them being charged with DUIs. I would guess most people are surprised and they admit it because they don’t think there is any danger.

By Brian Douglas Sloan

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Why Attorney Brian Douglas Sloan?
Phoenix DUI Lawyer

Why Attorney Brian Douglas Sloan?


18+ Years SOLELY Focused on DUI Defense


4,100+ DUIs Successfully Defended

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“I am one of only a handful of Phoenix DUI Lawyers that focuses solely on DUI Defense representation.”

I have spent my entire career focused on DUI Defense representation, having personally defended more than 4,100+ DUI clients in the past 18+ years.

If you’re looking for a divorce attorney, tax attorney, or civil attorney, then I can comfortably say: "I’m not the one for you".

Coming up with traditional, as well as outside-the-box motions and defenses for my clients, often with good results, is the hallmark of my practice.

Lawyers that say they are "aggressive", or "will fight for you", are a dime a dozen. They use these phrases because that is what they think people want to hear. The truth of the matter is, being "aggressive" rarely gets the client anywhere in these court systems. Being "aggressive" isn’t the same as being good, and is often used to put on a show for a client to hide the fact that they aren’t doing anything meaningful for the client.

The same is true for the lawyers that claim to do DUI Defense... and Criminal Cases..., and Accident cases..., and Divorces. A Jack-of-all-Trades is a master of none. By handling all different sorts of cases, they take away from their ability to truly focus on DUIs, and keep up to date on the latest changes in DUI Defense Representation.

What I offer is intelligent, quality DUI Defense, at an exceptional price.

I am one of only a handful of Arizona DUI Lawyers that focuses solely on DUI Defense representation.

I have not only taught other lawyers how to do DUI Defense Representation at statewide seminars, but I produce DUI Legal Guides used by defense lawyers across Arizona.

I am one of the most award-winning DUI Defense Lawyers in Arizona; have been recognized nationally, including in a 2022 issue of USA Today; and there are only a few lawyers in Arizona who have personally defended more DUI cases than I have. I am also one of the most reasonably-priced DUI Lawyers, as I pride myself on charging a Flat Rate only for the legal services you need, and not for the legal services you don’t.

I am also the lawyer who people call once they realize that their original lawyer screwed something up, gave them false hope or false promises, or simply just took their money and didn’t do much on the case. You would be surprised at how often this happens.

Save yourself the trouble of hiring the wrong lawyer, and hire the right DUI Defense Lawyer from the start.

You can reach me on my personal cell phone: 480-720-7839.

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Brian Douglas Sloan

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