Field Sobriety Tests
Field Sobriety Tests (FSTs) are failure-designed tests. Nearly every motorist, regardless of sobriety levels, fails field sobriety tests. The level and degree of failure is noted by the investigating police officer. Starting any test too early is considered a failure. Performing a test too quickly or too slowly is considered a failure. Failure to follow the officer's strict instructions is considered a failure. As an example, an officer may ask a motorist on a roadway stop to count backwards from 78, stopping at 59. Inevitably, most people count backwards from 78 but forget when to stop, finally interjecting at 56 a question, "When did you want me to stop?" According to the officer, the motorist has "failed" that field sobriety test at that point.
Because Field Sobriety Tests are failure-designed, a driver should not attempt these tests. These tests are not designed to show whether a driver is sober. Performance of these tests is completely voluntary, and a motorist should not voluntarily submit to these tests.
The officer asks the motorist to recite the alphabet without singing. Although people often times complain that an officer requested that the motorist recite the alphabet backwards, this is primarily a myth. More often, the officer will request that the alphabet be recited from C through T. There is no scientific basis for this test, and the test results are not designated as reliable tests for measuring sobriety.
Finger to Nose
The officer asks the motorist to extend his or her arms and close their eyes, sometimes instructing the motorist to tilt their head back, touching the tip of the nose. There is no scientific basis for this test, and the test results are not designated as reliable tests for measuring sobriety.
The National Highway Traffic Safety Administration (NHTSA) has investigated and researched several field sobriety tests since the mid-1980s. A battery of three tests has been developed as a result of this research, formally referred to as "Standardized Field Sobriety Tests" (SFSTs). Michigan does not formally recognize and has not adopted these standards, but police officers employ these tests in many jurisdictions. Michigan STORM (Sobriety Trained Officers Representing Michigan) is an organization of Michigan police officers that have received NHTSA training. The SFSTs are as follows:
Walk and turn
Video of the Walk and Turn Test ('Right Click' and 'Save As' to view) This test requires a driver to walk heel to toe and turn. It must be performed on a surface where a clean line is visible and where there is a level, non-slippery surface. Failure includes:
One Leg Stand
Video of the One Leg Stand Test ('Right Click' and 'Save As' to view) The motorist is required to stand with one leg raised approximately six inches off the ground for approximately 30 seconds. The officer observes the driver for any sign of swaying, hopping, or using arms for balance. If the motorist sways, hops, uses arms for balance or fails to maintain the position for the entire 30 seconds, the results are deemed to be a failure.
Horizontal Gaze Nystagmus (HGN)
Video of the HGN Test ('Right Click' and 'Save As' to view) Horizontal Gaze Nystagmus or HGN is an involuntary jerking of the eye that is purportedly caused by alcohol causing a jerking (nystagmus) of the eye as it moves from side to side. This is an extremely technical test that a motorist has no control over, and the results are completely subjective, based entirely upon the officer's observation. Most officers receive little training in this test, but it is one of the more common tests employed by police.
A recent article criticizing SFSTs was published by a Texas DWI criminal defense lawyer, Mimi Coffey. Ms. Coffey's article, DWI-Modern Day Salem Witch Hunts, provides insight into many of the problems that SFSTs suffer. You can visit Ms. Coffey's law firm web page located at http://www.dwitrialattorney.com.
More information that you need to know:
NHTSA Student Manual 2004 Edition
DWI Detection and Standardized Field Sobriety Testing Student Manual 2004 Edition
Walk and Turn test ('Right click' and 'Save as' to view)
One leg stand test ('Right click' and 'Save as' to view)
HGN test ('Right click' and 'Save as' to view)
- Psychophysical Tests for DWI Arrest (1977)
- The Visual Detection of Driving While Intoxicated Field Test of Visual Cues and Detection Methods (1980)
- Development and Field Test of Psychophysical Tests for DWI Arrest (1981)
- Field Evaluation of a Behavioral Test Battery for DWI (1983)
- The Detection of DWI Motorcyclists (1993)
- 1995 Colorado Validation Study of the Standardized Field Sobriety Test Battery.pdf
- 1997 Florida Validation Study of the Standardized Field Sobriety Test Battery
- 1997 NHTSA The Detection of DWI at BACS Below 0.10
- 1998 San Diego Study - Validation of the Standardized Field Sobriety Test: Battery at BACs below 0.10 Percent
- APRI Horizontal Gaze Nystagmus State Case Law Summary
- Horizontal Gaze Nystagmus The Science and The Law A Guide for Prosecutors Judges and Law Enforcement