In order to accurately administer the one leg stand field test, the officer must move the suspect to a hard, dry, level, non-slippery surface. Conditions must be such that the suspect would be in no danger if they were to fall. Certain wind or weather conditions obviously may interfere with and affect the validity of this test.

This test should not be given to persons who are more than sixty-five years of age. Also avoid the test if  the person is more than fifty pounds overweight. Or, it should not be given to people with physical impairments that interfere with balance. Individuals wearing heels more than two inches high should be given the opportunity to remove their shoes. This may diminish the reliability of the results. The officer is trained not to give this test if there is not adequate lighting to perform it. In total darkness, even the average, sober person may have difficulty with this test. This is a result of a lack of visual frame of reference that would otherwise be provided with proper lighting.

As with the walk and turn test, it is imperative that the officer observes the suspect from at least three feet away. They should remain as motionless as possible so that there are absolutely no distractions caused by the officer.

Instructions Phase

In the administration of this test, there are two separate stages involved. The first phase is called the instructions phase. During the instructions phase, the driver has to stand with feet together, with arms at the sides, while listening to instructions. This is designed to divide the driver’s attention between balancing and listening to the police officer’s instructions.

The test is begun by giving verbal instructions, followed by a demonstration. The police officer is trained to advise the driver to stand heels together and arms down at the sides, making sure not to begin the test until they are told to do so. The officer has to receive confirmation that the driver understood the instructions, and then document this acknowledgement. There aren’t any scoring opportunities until the next stage of the test, which is the balance and counting stage. The only other possibility is if the driver can’t perform the test, which would be scored as a maximum of four points and would be explained by the officer in the police report.

Balancing and Counting Phase

The next phase of the one leg stand is the balancing and counting phase. At the beginning of this stage, the officer has to explain the test requirements further by instructing the driver to stand on one leg. (The driver is allowed to choose which leg to stand on.) The driver has to hold the other foot in front about six inches from the ground, all the while keeping the foot parallel to the ground. While standing, the driver has to keep arms at the sides, and eyes on the elevated foot, while counting out loud “one thousand one, one thousand two”, etc. all the way until a full 30 seconds has passed. This basically divides the driver’s attention between balancing and counting.

The timing is important to note as impaired persons usually cannot stand for the full 30 seconds. Police officers are looking for four specific clues from drivers while they are performing the one leg stand:

  • Swaying while balancing
  • Using arms for balance
  • Hopping
  • Putting the foot down

Police consider a driver unable to complete the one leg stand when a driver either:

  • Puts their foot down three or more times during the 30-second testing period; or
  • Simply cannot do the test

Scoring the One Leg Stand Test

Point One

In regards to scoring the one leg stand, a driver may be scored a point for swaying while balancing. Police officers are trained not to be too critical in regards to this scoring as the driver taking the test is not a gymnast and some swaying is a natural human reaction. The swaying that can be scored is a marked sway, which would be a back and forth motion while the driver maintains the position.

Point Two

Another aspect of the scoring would be the driver using their arms for balance, raising them six or more inches from the side of the body. The police officer has to take into account the natural position of the arms. For example, some bodybuilders or men with large arms may have a natural position of more than six inches.

Point Three

A third scoring factor on the test is whether or not a driver hops on one foot during the test. This is scored only if the driver resorts to hopping on the anchor foot in order to maintain balance. This point should not be scored if the driver is having difficulty by moving the anchor foot back and forth. As part of training, police officers are supposed to be able to distinguish this and to allow the driver this movement.

Point Four

Finally, if the driver places their foot down, even if more than once, only one point can be given. The driver should be allowed to continue from the point of difficulty as the one leg stand could lose sensitivity if it is repeated several times. The driver has to be instructed to keep watching the raised foot and to count out loud, but no points are issued if this instruction is not followed. If the driver counts too slowly, it is important that the officer stop the test after 30 seconds have elapsed as this could affect the scoring and validity of the test. Police officers are trained to time 30 seconds of total test time so if the driver counts too fast, the officer will instruct them to slow down.

Maximum Score

A person can receive a maximum score on this test in two ways. The first way is if the driver puts the foot down three or more times during the 30 second count. The second way is if the driver can’t perform the test because of their intoxication level. If this happens, the maximum score is given; however, police officers have to be able to articulate why they felt that the defendant was incapable. The one leg stand test administered alone is considered approximately 65 percent effective if instructed and scored properly.

Officer Training

For the purposes of the police report and any courtroom testimony, the officer is trained that it is simply not enough to write the driver’s score on the three tests. The numeric scores are only important to the police officer at the scene in order to establish probable cause. A score is insufficient to secure a criminal conviction in a court of law and has to be accompanied by more descriptive evidence. The police officer has to be able to describe in detail how the driver performed. Remember, once again, that you do not have to take the field sobriety tests and you can politely decline when the officer requests that you participate in the tests.

Some of the questions concerning the one leg stand are:

  • Did the officer ask you to stand on one leg?
  • If the answer is yes, what directions did the officer give to you about this test before you began?
  • Did the police officer specifically demonstrate this test for you?
  • How long did the test take, specifically did you have to count to 30 or another number?
  • How was your performance on this test?
  • Did the officer comment on your performance on this test?