During a traffic stop, a police officer talking to a driver seeks to determine whether or not that individual violated the law. Many traffic stops lead to citations for excess speed or the failure to use a turn signal.
However, some traffic stops culminate in an individual’s arrest. There is an assortment of offenses that officers may uncover during a traffic stop, including intoxication at the wheel. If an officer suspects someone of drunk driving, they will probably ask that driver to exit their vehicle to perform a field sobriety test. Why are field sobriety tests often part of an impaired driving traffic stop?
Officers don’t yet have probable cause
There are rules about when a police officer can arrest someone and when they can compel them to undergo a chemical breath test. Generally speaking, law enforcement professionals need to have probable cause to suspect chemical impairment if they want to ask someone to perform a breath test. A driver’s performance on standardized field sobriety tests can give an officer the justification they need to ask for a chemical test or to potentially arrest that motorist if they refuse to perform the test.
Officers want to strengthen the state’s evidence
Perhaps the driver already admitted to having something to drink and displayed impaired ability on the road. An officer may already believe they have the necessary probable cause to arrest someone and require a chemical test. Still, they will seek together as much evidence as they can. Video footage from a dashcam or body camera of someone performing poorly on field sobriety tests can help develop the claim that someone was under the influence at the wheel.
Sometimes, attorneys can prevent the inclusion of field sobriety test results in a criminal trial. If officers make mistakes regarding how they conduct the test or if they pulled someone over without lawful justification, it may be possible to exclude field sobriety tests and other evidence gathered during a traffic stop from the state’s case. Understanding the criminal investigation process for drunk driving may help people respond to allegations of intoxication at the wheel in more informed ways.