Standardized Field Sobriety Tests

The National Highway Traffic Safety Administration has standardized three of the field sobriety tests used when officers suspect a driver of alcohol impairment. These are the walk and turn test, the horizontal gaze nystagmus test, and the one-leg stand test. In the case of the one-leg stand field sobriety test, standardization means that the officer is supposed to follow certain criteria in terms of selecting the testing area, administering test instructions, and determining what behavior during the test is an indicator of possible intoxication.

Requirements for the Test Location

In order for the test to conform to NHTSA standards, it must be conducted on a surface that is reasonably level, dry, hard, and non-slippery.

Interpreting the Results of the Test

An individual has a 65 percent chance of having a BAC of over 0.10 percent if he or she does any two of four things during the test. The first is using arms to balance. The second is hopping instead of standing still. The third is swaying back to front or side to side while balancing. The last is putting down the foot that is supposed to be held up.

Possible Problems With the Test

People who have health problems that affect balance (such as back, leg or middle ear issues), are 65 years of age or over, or who are obese or overweight by at least fifty pounds can have difficulty with this test regardless of alcohol impairment or lack therof. Additionally, test subjects wearing footwear with heels two or more inches in height should be offered the chance to remove them before the test.

If you are facing DUI charges and want to know whether the field sobriety test evidence being used against you could be considered invalid, contact the law offices of Vanden Heuvel & Dineen, S.C. to speak with an experienced Milwaukee DUI attorney.