One-Leg Stand Test Law and Legal Definition

One-Leg Stand Test (OLS) is one of the field sobriety tests that are given to a driving under influence suspect. OLS is a cheap, easy, and simple way of assessing postural control. OLS measures the time in seconds a person is able to maintain balance standing on one leg.

Procedures for the one-leg stand test include initiating the test by giving verbal instructions, accompanied by demonstrations. First, the officer is to instruct the subject to stand with his feet together and arms down at the sides. The officer should demonstrate. The officer should instruct the subject to, upon command, lift one leg approximately six inches from the ground, arms at his side, and while holding the position, count out loud for thirty seconds (one thousand one, one thousand two, etc.). [Jolley v. Harvell, 254 Fed. Appx. 483, 485 (6th Cir. 2007)].