Last week, we discussed a field sobriety test known as the Horizontal Gaze Nystagmus. This is a test you might have seen on television or in a movie, where a police officer has the suspect track a moving object with their eyes. The object is often a pen, a flashlight or the officer's finger.
Although there are a number of field sobriety tests used in different states, the HGN is one of three tests developed and recommended by the National Highway Traffic Safety Administration. In today's post, we'll discuss the second of these tests: the aptly named "Walk-and-Turn" test.
The Walk-and-Turn is used as a way to measure both a suspect's physical coordination and his ability to divide his attention (between listening to instructions and performing basic physical movements). In a typical Walk-and-Turn test, the officer instructs the suspect to:
- Take nine steps in one direction, walking heel-to-toe on a straight line
- Turn around on one foot
- Take nine steps in the opposite direction, again walking heel-to-toe
The rationale for this test is that an unimpaired person should have little difficulty performing the test, but it would be considerably harder for an intoxicated person to stay balanced, follow directions and coordinate the physical movements. According to the NHTSA, officers are trained to look for eight indicators that the suspect may be impaired. These include:
- Beginning the test before instructions are finished
- Experiencing balance issues while listening to instructions
- Being unable to consistently touch heel-to-toe while walking
- Needing to stop walking in order to regain balance
- Sticking arms out to the side to assist in maintaining balance
- Stepping off the line
- Taking an incorrect number of steps (more or less than 9 in each direction)
- Making an improper turn
Usually, two or more of these indicators are taken as a sign of impairment.
As with all field sobriety tests, however, the Walk-and-Turn test does not prove intoxication or alcohol impairment. A suspect's problems with balance, physical coordination and ability to follow directions could be affected by a number of other factors, including their overall physical health. Conversely, a suspect who is young and physically fit may be able to pass a field sobriety test despite being well above the legal limit.
Please check back next week as we discuss the third field sobriety test recommended by the NHTSA.