Although field sobriety tests (FSTs) are reliable when determining if a driver is intoxicated, they have limitations. And one of such limitations regards people with pre-existing medical conditions. Some medical conditions can affect one’s ability to perform in FSTs as expected.
Here is how this happens:
Balance issues
A person with medical conditions that impact their balance may fail an FST. For example, the inner ear, specifically the vestibular system, helps humans maintain balance. When it’s damaged by an infection or injury, one can have balance problems.
If the police ask such a person to submit to a horizontal gaze nystagmus (HGN) test, walk-and-turn test or one-leg stand test, it can be difficult for them to maintain balance.
Arthritis
An FST performance can be substantially impacted if a person has arthritis. Symptoms like pain, stiffness and reduced range of motion can make it difficult for one to maintain balance. They can also lead to coordination issues. Balancing on one leg with pain in the knees or ankles, or walking and turning with limited movement of joints, can be challenging.
Visual impairments
A person with cataracts or any other visual impairment that leads to reduced visual acuity can easily fail the HGN test. A visual impairment can cause involuntary eye movements that may mimic intoxication.
Mental health conditions
Mental health conditions like anxiety, stress and post-traumatic stress disorder (PTSD) can cause physical symptoms that might be interpreted as intoxication. For example, someone with anxiety being stopped by the police and ordered to perform several tasks can trigger shaking, sweating, difficulty concentrating or even slurred speech.
A sober driver may fail a field sobriety test due to a medical condition. If you have any condition that you believe affected your results, leading to a driving under the influence (DUI) charge, it’s vital to understand how to defend yourself.