A very brief snapshot of events that typically occur after being pulled over for DUI:
Reasonable Articulable Suspicion for the Stop in your DUI Case
The first issue in most DUI cases is whether or not the officer had a legal reason to stop the vehicle or person in question. The Fourth Amendment to the United States Constitution protects people from unreasonable searches and seizures. The officer must have reasonable suspicion for the stop. Otherwise the stop violates your Fourth Amendment rights. Officers usually base their decision to conduct a traffic stop because of an alleged violation of the law. Some common reasons for traffic stops in DUI cases are failure to maintain lane, failure to dim headlights, not using a turn signal, improper lane change, failure to obey a traffic control device. There are multiple legal challenges to "the stop" itself.
Field Sobriety Tests
Once you have been stopped by the police, you may be asked to submit to field sobriety tests. The National Highway Traffic Safety Administration (NHTSA) sponsored the research which led to the development of the roadside tests that are supposed to indicate whether or not someone is under the influence of alcohol or drugs. THESE ARE VOLUNTARY TESTS. You are not required to submit to any field sobriety tests. The three most common field sobriety tests are the Horizontal-Gaze Nystagmus Test, the Walk and Turn Test, and the One-Leg Stand Test. Officers are looking for certain "clues of impairment" which are usually unknown to the person taking the test. This is the reason that many people are surprised to see in a police report that the officer claims that they have failed some or all of the field sobriety tests. The roadside Portable Breath Test (PBT) is also a field sobriety test and it is not admissible in court as to the blood-alcohol reading that it provides. It is only admissible as to the positive or negative reading for the presence of alcohol. There are multiple potential flaws with field sobriety tests that may need to be challenged in a DUI case.
State Administered Tests of Blood, Breath and Urine
After someone is placed under arrest for DUI, the arresting officer may read the Georgia Implied Consent law to the person and ask them to submit to a State-administered chemical test of their blood, breath or urine. This test is also voluntary! Although the test is voluntary, a driver may be subject to a one-year suspension of his/her driving privileges in the State of Georgia for simply refusing to submit to the requested State-administered chemical test under the Georgia Implied Consent Law. Whether or not a person has voluntarily submitted to a State-administered chemical test is based on a review of the totality of the circumstances of the events that occur prior to/during the submission to any test. It is important that you raise any potential legal challenges to any test results. The breath test is the most common State-administered test. As stated above, the "breathalyzer" that you take on the side of the road is not admissible as to the blood-alcohol amount. Because the breathalyzer is not admissible, arresting officers may ask someone who has already been arrested for DUI to submit to a second breath test on the Intoxilyzer 5000 or 9000. The arresting officer may also ask for a blood test. In my experience, I believe that the arresting officer will ask for a blood test when the person has "blown" a low blood-alcohol level on the breathalyzer. An officer may be requesting a blood test because he/she believes that the person is under the influence of drugs that did not show up on the breathalyzer test. There are also multiple challenges to the machines that are giving the blood alcohol readings (Intoxilyzer 5000 or 9000). Errors in the administration of these tests or failure to follow the training manuals and procedures can produce completely inaccurate readings. A prime example of this is mouth alcohol. If someone burps, belches or vomits prior to submitting to these tests, their blood alcohol readings may be completely inaccurate.
Blog posts by Bill Hardman at DUI Blog and Case Results