What is a clue indicating impairment if the driver puts their foot down during the One Leg Stand?

Putting a foot down during the One Leg Stand test is indeed considered a clue indicating impairment. This field sobriety test is designed to assess balance and coordination, and a failure to maintain the position—such as putting a foot down—suggests that the driver may not have the necessary physical control that is expected when sober. The inability to keep one leg raised for the required duration indicates a potential impairment, whether due to alcohol consumption, drugs, or other factors affecting motor skills.

The assessment relies on observable behaviors that reflect a driver's ability to operate a vehicle safely. When a driver exhibits difficulty in coordination during this test, law enforcement may interpret it as a sign of impairment, supporting further investigation or action. Thus, this observation serves as an important piece of evidence in evaluating the driver's condition during a DUI traffic stop.