The evidence most people think of when they consider drunk driving charges will be chemical test results. Many police officers have chemical breath test units in their vehicles that they can use to determine someone’s blood alcohol concentration (BAC) following a motor vehicle collision or during a traffic stop.
However, police officers often obtain the right to request breath testing through other investigatory means. The questions that they ask someone and the field sobriety tests that an officer may have someone perform can play an important role in justifying the administration of a breath test and in validating suspicions of impairment when prosecuting someone.
Sometimes, questioning the validity of field sobriety test results can be as important as raising questions about a chemical test. What are some of the situations in which a driver could exclude evidence related to a field sobriety test from the criminal proceedings in their case?
When the officer fails to record the test
For the results of a field sobriety test to hold up in criminal court, an officer typically needs to ensure the test is visible from their dashboard camera or that they have a body camera recording while administering the test. In a scenario where the only evidence about the field sobriety test is the officer’s testimony, their fallible memory and subjective interpretation of your performance may not hold up in court.
When the officer takes liberties with testing
There are three standardized field sobriety tests that most police officers use to determine if someone has signs that likely indicate chemical intoxication. These include the horizontal gaze nystagmus test, the one-leg stand test and the walk-and-turn test.
When an officer either administered completely different tests than the standard ones or made questionable changes to the process for the three standard tests, the driver or their attorney may be able to use those deviations from the standard as part of the defense strategy.
When an officer didn’t have justification for a traffic stop
The ability to include field sobriety test results and even chemical test results in the prosecution’s evidence will depend on the legality of the traffic stop. If a police officer pulled someone over without an appropriate justification, it may be possible for a lawyer to exclude the evidence gathered during that stop from criminal proceedings.
Challenging the field sobriety test results is one of several potentially viable defense strategies you could use while facing DUI charges.