The Anatomy of a DUI Investigation

Limitations of the Walk-and-Turn and One-Leg Stand Tests

Attacking the divided attention tests includes addressing any applicable circumstances where NHTSA has indicated the tests would be inappropriate, including:

• Age – NHTSA has identified that individuals 65 and older have difficulty performing these tests due to age. For a client who is 60+ you could also indicate that even though administration of the test is allowed, the person is nearing the age where the test results would not be meaningful and that should be taken into account.
• Location of tests – These tests are to be performed on a reasonably dry, hard, level, and non-slippery surface. If the tests are performed on a hill, a steep grade, in the rain, or in a gravel parking lot with uneven terrain, a false positive for certain clues could result.
• Weight – A person 50 pounds overweight will likely have difficulty performing the one-leg-stand, according to NHTSA research.
• Injuries – A person with back, leg, or inner ear problems will have difficulty performing either test. An officer should identify and make note of any medical concerns that are present. However, officers frequently ask “do you have any physical limitations that would prevent you from performing field sobriety tests?” before they instruct a driver on the individual tests. Since most people have never done a field sobriety test, they normally say they are not aware of anything that would keep them from performing the test. If the officer is conducting a fair investigation, he should ask, “do you have any medical concerns related to your legs, back, or inner ear?” Asking someone “can you walk?” is not the same asking them “have you had medical issues with your legs?” Someone who answers the former question “yes” may still be a poor candidate for these tests.
• Footwear – Any person wearing footwear with two-inch (or higher) heels should be given the option to remove footwear before performing these tests. However, performing the tests barefoot could create additional reasons why an individual might have trouble performing the tests to the satisfaction of the officer.

Challenging the Results of Standardized Field Sobriety Tests

Attack inadequate instructions. For example, “So you never told my client not to begin the Walk-and-Turn before finishing your instructions?”

Attack incorrect test interpretation, i.e. clue noted when it should not have been. For example, “So you say my client used his arms for balance, but he barely raised his arms, not six inches as required by NHTSA?”

Attack the officer who incorrectly finds non-compliance with instruction as a clue of the test. “So you stated that my client exhibited the clue of not counting his steps out loud during the Walk-and-Turn test, but that is not one of the eight clues identified by NHTSA during that test, is it?”

During cross-examination, begin with questions about the particular stages of the SFSTs such as, “How did you instruct my client to perform the One-Leg Stand Test? Tell me exactly how you instruct somebody to perform that test? Are there any other instructions that you give during that test?”

If the officer is giving inadequate or incomplete instructions, refer to the NHTSA student manual, “You received a copy of a student manual during your training? Please look at this manual. Can you identify this manual as substantially similar to the one that you received in your training?”

Then ask, “Well, you were supposed to tell the person to keep his arms down by his sides and you never told him to do that, weren’t you? So you’ve indicated that he used his arms for balance but you never specifically instructed him not to do so, did you? You never told the person how he was supposed to count or how high to count, did you? You never told him how he was supposed to turn at the end of his first nine steps, did you?”

An effective attack on SFSTs begins by knowing better than the officer how these tests are to be performed and how the clues are to be evaluated. Without training on these tests you are significantly handicapped in your ability to effectively cross-examine the officer.