Whenever a police officer suspects that you're drunk driving – called operating under the influence (OUI) in Maine and pulls you over, the main goal is to find sufficient evidence that you've committed a crime.
Field Sobriety Tests
One of the ways that police officers will gather evidence of OUI is to have you perform field sobriety tests. These are specific tasks that have been approved by the National Highway Traffic Safety Administration to test certain physical abilities that may become compromised whenever you drink alcohol. For example, the Horizontal Gaze Nystagmus test measures involuntary movements in your eye, which supposedly become more pronounced when alcohol is introduced in your bloodstream.
Several field sobriety tests are designed to challenge your ability to do multiple things at once while performing a physical task. The Walk and Turn is one of these tests.
Walk and Turn
The Walk and Turn is a divided attention test because it challenges both your coordination as well as your ability to listen to and understand specific instructions.
The officer will tell you to take nine steps along a straight line in a specific heel-to-toe fashion. After the ninth step, you're supposed to perform a specific type of turn on one foot and walk the nine steps back to your starting spot, using the same heel-to-toe method.
While you do the Walk and Turn, the police officer will be watching closely for seven different clues:
- Whether you can keep your balance while the officer is giving you instructions while maintaining the instructional position,
- Whether you start walking before the officer has finished giving all of the instructions,
- Whether you have to stop walking at any time during the test,
- Whether you step off the line during the walking phase of the test,
- Whether you actually touch your heel to your toe while walking along the line,
- Whether you need to use your arms to help balance,
- Whether you make an improper turn, and
- Whether you take nine steps or not.
If the officer sees any two of these clues, then you will have failed the Walk and Turn, and provided law enforcement with valuable evidence that they'll claim shows that you were operating under the influence.
The Walk and Turn's Glaring Problems
Like all field sobriety tests, the Walk and Turn is plagued with problems that frequently result in false positive readings. Many of the clues are subjective – different cops are likely to have different notions of what “swaying” or “maintaining balance” means. Additionally, your surroundings can play a huge factor in whether you pass or fail the Walk and Turn: How smooth or flat the ground is, whether there are cars rushing past, and how athletic you are can impact your performance. Even how the officer gives instructions on completing the test can become a factor if they're quickly or poorly given.
In the end, the Walk and Turn has been found to be accurate only 68% of the time.
OUI-Defense Attorney William T. Bly
It is important to remember that, in Maine, field sobriety tests are voluntary. Consenting to a field sobriety test can give law enforcement evidence that you were driving under the influence, even if you weren't.