Blood, breath, urine DUI tests in Arizona: Which is more reliable?

In many states, including Arizona, getting a driver's license is contingent upon agreeing to submit to a breath, blood or urine test if pulled over for suspected DUI. This is known as "implied consent."

Any officer who has probable cause to suspect a driver in Arizona is operating a vehicle under the influence of alcohol or drugs can request that the driver submit to one of these tests to determine his or her impairment level. Many drivers abide simply because of the penalties associated with refusing.

However, which test is chosen is left to the discretion of the officer. And each test can produce a different outcome.

Fallibility of Breath, Blood and Urine DUI Tests in Arizona

The three DUI tests in Arizona are extremely fallible, have been scrutinized and, in some instances, have been deemed unreliable. The main reason is there are simply too many factors that can affect the outcome of the test.

For instance, a driver who submits to a breath test shortly after having a drink will likely have a higher blood alcohol content (BAC) reading because the alcohol remains in the mouth. This is known as residual mouth alcohol and will inflate results. The presence of vomit or acid reflux (gastroesophageal reflux disease, also known as GERD) inside a driver's mouth can also affect a breath test and cause hyper-inflated results.

A driver who is pulled over soon after drinking and is given a blood test (which can be taken up to an hour after being pulled over) may have a higher BAC level at the time of the drawing because the BAC continues to rise for a period after alcohol has entered the body.

Countless other complex factors can skew results, ranging from a body's cell volume makeup and presence of methyl compounds to a failure to adequately test the breath device.

Immediately Consulting With a DUI Attorney

Due to the inaccuracies of these tests, a driver should not underestimate the importance of immediately seeking the help of a DUI lawyer if pulled over and arrested on suspicion of DUI.

In many situations, a driver's BAC reading has been thrown out and prohibited from use in court to prove DUI charges because of the inaccuracy of the software used or incompetence of the user or lab technician.

A lawyer knowledgeable in this area of criminal law can scrutinize the circumstances surrounding the arrest and BAC test and mitigate potentially damaging effects down the line.