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What Are The Scientific And Factual Ways People Are Charged With DUI In Arizona?

Interviewer: In Arizona, there is a facet of the law called “impaired to the slightest degree.” Does that mean someone below a 0.08 will still get charged with DUI?

Brian: Yes, in Arizona, there are two standard initial ways of being charged with DUI. The first one, you are driving or your ability to drive was impaired to the slightest degree by the use of alcohol, drugs- illegal or prescription, and/or vapor-releasing substances.

That is a more factual way of proving DUI. It is basically impairment. Also, it is driving or being in actual physical control of the vehicle.

The second way is more scientific. You were driving and you had a blood alcohol level at or above a 0.08, tested within two hours of driving; or you had illegal drugs or medication in your system. Illegal can be prescription medication that is not taken as prescribed.

So impairment can be by way of prescription medications, even if you are taking them completely as prescribed. It is not a defense to you, being impaired by prescription medications. It can also be impairment by vapor releasing substances, which we most commonly see with paint huffing. You can see it, absolutely, with alcohol.

In Arizona, there are presumptions of impairment. Someone tested at or above a 0.08 alcohol level is presumed, under Arizona law, to be impaired. If they are between a 0.04 and a 0.08, the law has no presumption. If they are between a 0.01 and a 0.04, they are presumed not to be impaired.

However, in theory the prosecutor could still choose to go forward at trial and argue impairment, despite the law’s presumption that someone is not impaired to that degree.

For example, I was talking to that guy today whose blood alcohol level came back at a 0.054. Under Arizona law, there is no presumption of impairment. However, there was a horrendous car accident they want to blame on my client, so they are doing the exception to the rule. They decided to charge him with DUI.

There is no presumption. It is a case that would normally be dismissed. Prosecutors would decide not to file it. However, there was a pretty bad accident, and they are going forward with such a low blood alcohol content and no drugs.

Interviewer: A typical person on a chemical registers a 0.08 or above. Does the person actually face two different charges: impaired and driving or operating a vehicle; and the concentration of alcohol in their blood is above a certain level?

Brian: Yes, just about everyone charged with DUI is charged with two or more counts. That is two or more ways the prosecutor can try to prove them guilty at trial. Under count one, they can try to prove the person was impaired to the slightest degree. Under count two, they can prove they were above the legal limit, a 0.08.

By Brian Douglas Sloan

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Brian Douglas Sloan


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Why DUI Attorney Brian Douglas Sloan?


19+ Years SOLELY Focused on DUI Defense


4,200+ DUIs Successfully Defended

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  • Only DUI "Power Lawyer" in the Nation Featured in USA Today, 2022

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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 Arizona DUI Defense representation, having personally defended over 4,200+ DUI clients in the past 19+ years.

If you’re looking for a divorce attorney, tax attorney, or civil attorney, 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 they think people want to hear them. Being "aggressive" isn’t the same as being good and is often used to put on a show to hide the fact that they aren’t doing anything meaningful for the client.

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

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

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

I am one of Arizona's most award-winning DUI Defense Lawyers, recognized nationally, including in a 2022 issue of USA Today.

There are no other private DUI Defense Lawyers in Arizona that have personally defended more DUI cases than I have. And as a bonus, I offer a flat rate for my legal services without any hidden charges. This guarantees that I offer some of the most competitive rates among all Arizona DUI Attorneys, while being the preeminent leader in the field of DUI Defense Representation.

Over the years, countless people have come to me after discovering that their first lawyer made a mistake, gave them false hope or false promises, or simply took their money and didn't do much to advance their case. And you would be surprised at how often this happens.

So, instead of wasting time and money on the wrong DUI Defense Attorney, do yourself a favor and get the proven and documented best DUI Lawyer in Phoenix and the surrounding areas of Maricopa County.

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

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Brian Douglas Sloan

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