Field Sobriety Tests

The tests that officers make a DWI suspect do on the side of the road are called Standardized Field Sobriety Tests.  They are called “Standardized” because every officer in the United States is expected to do them the same way and look for the same things.  The organization that sets forth the guidelines for doing these tests is the National Highway Traffic Safety Administration “N.H.T.S.A.”.

It is important that your attorney is very familiar with the NHTSA guidelines.  Officers sometimes make fundamental errors in their application of the tests.  Officers typically make at least small errors in the application of the tests.  Often, these mistakes go unchallenged in court because a defense attorney is not familiar enough with the N.H.T.S.A. guidelines to catch every mistake.

 Walk and Turn

The “Walk and Turn” is the field sobriety test with which most people are familiar.  It involves walking down a line, turning and walking back.  There are very specific things that officers must observe including: starting too soon, not holding the starting position properly, stopping during the test, stepping off the line, taking too many steps, turning improperly and raising one’s hands during the test.

Anyone that makes any two of these mistakes, in the officer’s opinion, fails the test. One Leg Stand The “One Leg Stand” is the field sobriety test that involves standing on one leg for 30 seconds.  The four things an officer looks for on this test is: keeping one’s foot up, swaying, raising one’s hands and hopping.  It is possible to keep one’s foot up the entire time and fail the test. Anyone that makes any two of these mistakes, in the officer’s opinion, fails the test.

 One Leg Stand

 The “One Leg Stand” is the field sobriety test that involves standing on one leg for 30 seconds.  The four things an officer looks for on this test is: keeping one’s foot up, swaying, raising one’s hands and hopping.  It is possible to keep one’s foot up the entire time and fail the test.

Anyone that makes any two of these mistakes, in the officer’s opinion, fails the test.

Horizontal Gaze Nystagmus

Easily the most misunderstood of all the Field Sobriety tests.  This is the test where the officer asks a suspect to follow a light.  What the officer is looking for are very specific types of shaking of the eyes which is an optometric phenomenon known as “Nystagmus”.

There are dozens of types of Nystagmus, however the only one that the officer is looking for is “Positional Alcohol Nystagmus”.  Having alcohol in the body can cause a shaking of the eyes.  The accuracy of officers doing these tests is hotly debated.  There are some that maintain that well trained officers can do an excellent job detecting nystagmus.  Others are concerned that having non-optometrists perform these apparently scientific tests can be misleading.

The “Horizontal Gaze Nystagmus” test is very dangerous to a DWI defendant.  Not only does the test seem scientific, but it is the only one that the jury can not see for themselves, because the eyes are too small to be seen.  If a defense attorney does not know how to challenge an officer’s conclusions, all the jury has to rely upon is a scientific test saying the defendant is guilty.