Arizona Horizontal Gaze Nystagmus (HGN) Practice Test

During Phase Three of DWI detection, the two major evidence gathering tasks are comprised of standardized field sobriety tests (SFST) and preliminary breath testing (PBT). SFSTs are systematic tests administered to assess a driver’s physical and cognitive abilities, and they typically include tasks such as Horizontal Gaze Nystagmus, Walk-and-Turn, and One-Leg Stand. These tests help law enforcement officers establish probable cause for a DWI arrest by evaluating an individual’s responsiveness and coordination under conditions that are challenging when under the influence of alcohol or drugs.

The PBT, on the other hand, offers a preliminary measurement of a driver’s blood alcohol concentration (BAC) and helps to confirm or supplement the observations made during the SFSTs. Together, these two evidence-gathering methods provide a comprehensive assessment of the driver’s impairment level.

The other options do not effectively encapsulate the primary tasks of Phase Three, as they either involve unrelated elements or lack the standardized aspects essential for DWI detection.