There are a variety of different tests that are used by law enforcement when they’re investigating drunk driving or DUI offenses. These tests can generally be broken down into two broad categories: field sobriety tests and chemical (blood and/or breath) tests.
Field Sobriety Testing
The roadside tests, which are also referred to sometimes as standardized field sobriety tests, include the “eye” test where one may be asked to follow the officer’s finger or flashlight as it’s waved in front of their face, the one-leg stand where a person stands on one foot, and a walk-and-turn where a person is asked to take nine steps in one direction and turn around and then take nine steps back to the starting point. What’s important to understand about these field sobriety tests is that they are voluntary in the sense that the police cannot suspend your driver’s license based solely on your refusal to participate in them. Before submitting to such tests, it is important to understand that if the tests are conducted properly and it’s shown that your participation was voluntary, your results on the test (which are subjectively judged by the police officer) could potentially be used against you in court. The test could also be used by the officer to help justify his or her decision to place you under arrest for DUI, which could then allow them to require a blood or other chemical test to be used against you in court as well.
Blood testing
Police agencies who investigate DUIs and arrest people for drunk driving often use blood testing instead of breath testing to prove the person’s blood alcohol concentration level in court. Blood testing does afford certain advantages to the prosecutor in the sense that it’s considered more accurate and reliable than breath testing. Ordinarily when a person is asked to submit to a blood test after being arrested for DUI, they are first informed that due to Arizona’s “Implied Consent” law they will lose their driver’s license for a period of 12 months if they refuse to voluntarily submit to the test.
In most instances, it makes sense to submit to the testing. If refuse the test, it is likely you not only are you going to lose your license for a year, but the officer may also be able to obtain a search warrant from a judge which will allow them to forcibly take your blood if necessary. It is usually advisable to ask to speak privately with an attorney prior to making that decision.
