What is the primary reason an officer establishes probable cause for a Field Sobriety Test?

Establishing probable cause for a Field Sobriety Test (FST) is crucial in the process of determining whether an individual should be arrested for suspected driving under the influence. The primary goal of gathering probable cause is to assess the situation and make an informed decision about the need for an arrest based on the officer's observations and the test results. If an officer has probable cause, it allows them to proceed with the arrest if further evidence indicates that the individual is impaired.

While gathering evidence for court, determining sobriety, and verifying identity are certainly important aspects of the overall process, they do not directly address the immediate need for an officer to justify an arrest decision based on the circumstances at hand. The key element is the officer's judgment to ascertain whether the individual poses a danger to themselves or others while operating a vehicle. This decisive factor is what drives the requirement to establish probable cause before proceeding with more formal evidence collection or legal proceedings.