Alcohol Tolerance: Is it a Defense to a DUI?

by the Phoenix DUI Lawyers at Ariano & Reppucci

Some people boast that they have a high alcohol tolerance, so they can drink more than the average person and still be relatively sober. It is true that alcohol tolerance does vary by person.1 Studies about alcohol tolerance show diverging results. Some studies have shown that a person’s blood alcohol concentration (BAC) does affect a person’s ability to recall information but does not have much effect on a person’s physical performance.2 One study of 54 subjects did show that those with a BAC of 0.2% or more (which would lead to a very serious DUI charge), 24% of the subjects did not show any sign of clinical intoxication.3 Tolerance for alcohol could either be supported by genetics or by long term regular drinking that allows an individual to build up a tolerance.4

Conversely, some studies show that even if your metabolism is tolerant to alcohol but not behaviorally tolerant.5 There have been other studies done a few years ago that show that even those with high alcohol tolerance are more likely than a sober driver to cause a fatal motor vehicle crash when their BAC is above 0.08% to 0.10%.6 These studies show that even though you may believe you are capable of driving because of your higher alcohol tolerance, your mental and physical dexterity may be impaired nonetheless.7

If I have a high tolerance to alcohol and I drive a vehicle, can I still be arrested for a DUI?

It is not likely. In Arizona, a BAC of 0.08% or more will land you with a Driving Under the Influence (DUI) charge if you are in physical control of a vehicle. The National Institute on Alcohol Abuse and Alcoholism estimated that it would take five (5) or more drinks in about two hours to bring your BAC to a 0.08% and above.8 Currently, the law does not make room for alcohol tolerance as a way out of this type of charge. Once your BAC comes back at 0.08% or more, you will be charged with a DUI if you were in physical control of a vehicle.

BAC is determined through different sobriety tests. Most  commonly, these are the blood sample, breath, or urine sample tests administered by police officers. There have been criticisms of the tests before because of their varying accuracies. Your DUI attorney may be able to argue that the field sobriety test was improperly administered, but this depends on your situation.

Since alcohol tolerance varies so much by individuals and perhaps each individuals’ metabolism, it would be difficult to create a uniform DUI law and also factor in an alcohol tolerance defense or standard. However, a higher tolerance to alcohol can pose some problems to law enforcement. Many drivers with BACs of over 0.08% are passed up at DUI checkpoints because the officers are trained to look for signs of alcohol impairment such as bloodshot eyes, fumbling fingers, and slurred speech.9 Those with high alcohol tolerance may not necessarily exhibit all these signs.

If you have been arrested for a DUI, it is best to contact an experienced DUI attorney. Your attorney will be able to assess your charges, the circumstances surrounding your arrest, and your best defenses.

[1] Tolerance To Alcohol,, (last visited Dec. 10, 2014).

2 Id.

3 How Alcohol Tolerance Develops,, (last visited Dec. 11, 2014).

4 See Tolerance For Alcohol,, (last visited Dec. 11, 2014).

5 Michigan Drunk Driving Lawyers, (Nov. 13, 2010),

6 Sandra C. Lapham, The Limits Of Tolerance: Convicted Alcohol-Impaired Drivers Share Experiences Driving Under The Influence, (2010), available at

7 Id.

8 Id.

9 Id.