As many drivers in Arizona will know, if your car is stopped by officers, there is a chance that they will ask you to submit to tests to determine your blood alcohol concentration. This can be somewhat daunting, as you may worry that the results could incriminate you, even if you are sober. It can often come down to the accuracy of the test and how well-maintained the device is.

The most common means of testing you BAC is with the use of a Breathalyzer. These machines work by using infrared spectroscopic analysis through which the alcohol content of vapor from your breath is measured. If the concentration matches or exceeds the legal limit of 0.08 percent, you could be charged with drunk driving.

However, as this article on BAC tests explains, they are not always accurate. Results from a blood draw, for example, can vary by as much as 15 percent from the readings taken by the Breathalyzer. This number could be even higher if the machine is malfunctioning. If you have any doubts about the reading, it is important to make this known to your attorney.

The penalties for drunk driving can often be severe, particularly if it is not your first conviction. You could face fines, the loss of your license or even a prison sentence. If you find yourself in this position, the advice of an attorney could be beneficial. He or she can explain the charges you face and may be able to help you build your defense and look for flaws in the investigative process.