Police officers who suspect drivers of chemical impairment need objective evidence. Chemical testing can affirm if a motorist is over the legal limit for their blood alcohol concentration (BAC). However, chemical testing often occurs after a police officer decides to arrest a driver for intoxication.
They need to gather evidence supporting their suspicions before they arrest the motorist. One of the ways that police officers establish that an individual has had too much to drink is to conduct a series of field sobriety tests.
These tests are physical tasks performed by the driver under the observation of the officer. What typically happens during field sobriety testing?
There are three standardized tests
Police officers receive training regarding field sobriety tests. They should follow best practices when they ask motorists to step out of their vehicles and submit to testing. For example, they should administer the test in a location where they can record video footage of the driver’s performance.
They also have to properly administer the three tests recognized as standard. Drivers may have to perform the walk-and-turn test. They must walk in a straight line, turn completely around and walk back along the same line.
Officers may also ask drivers to perform the one-leg stand test. The driver shifts their weight onto one leg and attempts to maintain their balance. Finally, officers may ask drivers to perform the horizontal gaze nystagmus test. The officer asks the driveway to follow an object, such as a pen or a finger, with their eyes. They watch for muscle spasms that indicate chemical intoxication.
Tests are not mandatory
Drivers who refuse to submit to chemical breath testing after arrest are at risk of consequences for their test refusal. The implied consent statute makes post-arrest testing mandatory. However, that law does not apply to field sobriety tests. Police officers cannot force drivers to perform these tests and generally cannot punish them for refusing to do so.
Even in cases where drivers fail field sobriety tests, there could be a reasonable explanation. Medical issues, for example, could compromise an individual’s balance or affect muscle spasticity. Those facing impaired driving charges may need help countering the state’s allegations. Learning about the rules for field sobriety testing can help people evaluate different potential defense strategies.