LEGAL GUIDE
Written by attorney Morris Hugh Wiltshire Jr.

DUI Investigation Roadside Testing: The Horizontal Gaze Nystagmus (HGN) Test

This is an overview of the NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION (NHTSA) rules for STANDARDIZED FIELD SOBRIETY TESTING (SFST) for HGN. This testing is used by law enforcement in the most important phase of a roadside DUI investigation the officer's observations of the driver.

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