Most people think that driving after drinking will result in a DUI charge. This is not necessarily the case as you will be only charged when you operate a vehicle when your blood alcohol concentration (BAC) level is more than 0.08 percent.

Police officers follow standard guidelines established by the National Highway Transportation and Safety Administration (NHTSA) that specify the correct procedure to follow when conducting a DUI test such as Standardized Field Sobriety Tests (“SFSTs”).

An experienced DUI attorney will be familiar with the guidelines relating to the detection of DUI. This knowledge will be used to ensure that the test was performed correctly by law enforcement personnel. Generally, the NHTSA guidelines regarding DUI detection can be divided into three phases that are discussed below.

Phase 1: State of Driving

In the first phase, the police officer tries to determine whether the person was driving the vehicle properly. The officer closely observes the vehicle to determine the manner in which the driver is driving. In this phase, the officer will decide whether or not to stop the driver.

Phase 2: Personal Interview

In the next phase, the police officer asks the person driving in a suspicious manner to step out of the vehicle. This begins the initial contact with the person. The police officer observes the person by asking a few questions. If the person does not give a proper response, the police officer will then commence pre-arrest screening, which is phase 3 of the DUI detection process.

Phase 3: Screening of the Individual

The last phase involves screening the individual to determine whether there is cause for an arrest. In most cases, the police officer performs a field sobriety test. The NHTSA recognizes three tests as standard sobriety tests. These include:

  • One-leg stand test
  • The walk and turn test, and
  • The horizontal gaze nytagmus test

Apart from the above, the police officer may perform non-standardized tests such as a preliminary breath test to determine whether the individual was drunk while driving. The police officer will report his/her findings in a police report. This report is presented in court during court hearings.

Every DUI case is different and you should hire a licensed attorney to represent your case in court. An experienced attorney will make sure that your rights are protected. The attorney can assemble your defense in the best way with the goal of minimizing penalties. The DUI lawyer will look at each phase of the police investigation, and challenge the findings in court in case any discrepancy is detected with the goal of achieving the best possible outcome for you.