Experienced Rochester DWI lawyers have seen a great variety of field sobriety tests used by law enforcement.

In some cases, police officers have even been known to ask drivers to perform tests that are difficult when sober, such as reciting the alphabet backwards.

The National Highway Traffic Safety Administration (NHTSA) has studied the accuracy of some field sobriety tests and made recommendations to standardize which tests are used and how these tests should be administered.

There is, however, no obligation for law enforcement to use these standardized tests.

Even when they are used, law enforcement frequently deviates from the NHTSA’s recommendations regarding how the tests should be administered.

The three field sobriety tests the NHTSA recommends using to test for DWI are the horizontal gaze nystagmus test, the walk-and-turn test, and the one-leg stand.

According to the NHTSA, when these three tests are used in combination and administered in the manner recommended by the NHTSA, they are 91% accurate in determining whether a driver has a blood alcohol content of .08% or greater.

While this accuracy rate is very high, in our experience law enforcement rarely administers the field sobriety tests in the manner recommended by the NHTSA.

For example, the NHTSA recommended version of the walk-and-turn test requires that the driver walk in a straight line exactly nine steps heel-to-toe, turn on one foot, and return nine steps in the opposite direction.

While the driver is doing this, the officer is supposed to look for eight different potential indicators of impairment – the presence of any two indicators is considered a failure of the test.

In practice, this test is frequently performed on the side of the road in the dark, and the arresting officer is seldom as “scientific” in conducting the test as the NHTSA recommends.

If you have been arrested for DWI, you need an attorney who knows how to evaluate the evidence against you, call us at 585-484-7432 for legal help.