What is the purpose of a field sobriety test?

The purpose of a field sobriety test is to assess a driver's physical and cognitive abilities. These tests are designed to evaluate how well an individual can perform tasks that require balance, coordination, and attention. Typically administered during a DUI traffic stop, the tests help officers determine whether a driver may be impaired by alcohol or drugs.

By observing a driver's performance in tasks such as walking in a straight line, standing on one leg, or following a moving object with their eyes, law enforcement can gather evidence that supports their assessment of the driver's impairment. These evaluations are not meant to definitively measure blood alcohol concentration but rather to provide an observable indication of whether the driver is under the influence.