Police officers frequently stop motorists who appear to be under the influence of drugs or alcohol. They may also screen drivers for signs of impairment after collisions. Most motorists in the St. Louis, Missouri, area or in Illinois understand that police officers can conduct chemical tests. They may also be aware of field sobriety testing. Police officers can guide drivers through certain physical tasks to try to evaluate them for intoxication.
There are three field sobriety tests recognized as standard. What do those tests involve?
Standing on one leg
Alcohol and other mind-altering substances can affect a person’s sense of balance or equilibrium. The one-leg stand test is a common way to evaluate a driver’s intoxication.
Walking and turning
The walk-and-turn test looks at both balance and gait. People who are under the influence are likely to stumble and may struggle to readily follow verbal instructions. If drivers cannot walk in a straight line, turn around when instructed to do so and walk back along the same line, that may lead officers to suspect them of intoxication.
Following an object with the eyes
The horizontal gaze nystagmus test looks for a subconscious symptom of impairment. Certain muscular tremors become more pronounced after people consume alcohol and similar substances. Officers may watch how the eyes move as people follow an object to evaluate their impairment levels.
Drivers generally have the right to decline field sobriety testing. They can also fight criminal charges by presenting evidence about why they failed field sobriety tests. Making use of one’s right during a traffic stop or fighting back against pending drunk driving charges can help motorists avoid criminal convictions and protect their driving privileges.