What additional factors should be evaluated alongside HGN results?

Evaluating physical signs and other behaviors alongside HGN results is crucial for several reasons. The Horizontal Gaze Nystagmus (HGN) test is specifically used to assess an individual's level of impairment, particularly related to alcohol consumption. However, the reliability of the HGN test can be affected by a range of factors beyond just the eye movements.

Physical signs such as staggered walking, slurred speech, or the smell of alcohol can provide additional context and help confirm or support the findings from the HGN test. Similarly, observing other behaviors, such as the subject’s ability to follow instructions or maintain balance, can further clarify the extent of impairment. This comprehensive approach ensures that the assessment is as accurate and holistic as possible, leading to more informed decision-making regarding a subject's sobriety and driving capabilities.