What are field sobriety tests primarily used for?

Field sobriety tests are primarily used to assess a driver's level of impairment for driving under the influence (DUI). These tests are performed during a traffic stop when an officer suspects that a driver may be under the influence of alcohol or drugs. The purpose of these tests is to gather evidence of impairment based on the observed performance of the driver.

The tests often include tasks that measure balance, coordination, and the ability to follow instructions, as impairment will typically affect these skills. Successfully passing these tests can indicate that a driver may not be impaired, while failing them can provide crucial evidence supporting a DUI arrest. Thus, field sobriety tests are a key component of law enforcement's efforts to ensure road safety and to identify and remove unsafe drivers from the roadway.