Standardized Field Sobriety Testing (SFSTs)
The Standardized Field Sobriety Test (SFST) is composed of three tests:
- Horizontal Gaze Nystagmus (HGN)
- Walk-and-Turn (WAT)
- One-Leg Stand (OLS)
The tests were developed by the National Highway Traffic Safety Administration (NHTSA) in the late 1970’s. In 1981, law enforcement officers began using the NHTSA sobriety tests at roadside to help determine whether motorists who are suspected of DWI have blood alcohol concentrations (BACs) greater than 0.10 percent.
The validity of SFSTs depends heavily upon the officer’s training. Even under perfect conditions, NHTSA has conceded that the HGN is wrong 23% of the time, the WAT 32%, and the OLS 35% of the time. Additionally, if any of the procedures used for administering the tests are not followed precisely, these tests can result in even higher percentages of invalid results. This being the case, you need an experienced lawyer in DWI to review the procedures followed in administering the tests to ensure that they were done properly.
If you’re fighting a DWI, you need to contact a Texas DWI Attorney for assistance.