The Horizontal Gaze Nystagmus Test, the Walk and Turn Test, and the One Leg Stand Test are the three most common field sobriety tests used by Louisiana law enforcement personnel. However, these tests aren’t always accurate. A person can fail any or all of these tests without having been drinking or using drugs. A previous leg injury, for example, can make a person unstable on one leg. Additionally, an officer's personal assessment isn't always accurate.