In Minnesota, if an officer has reasonable cause to believe you are driving while impaired (DWI), they may pull you over. If they do, they might ask you to take part in a series of voluntary tests. These exercises are known as field sobriety tests. Officers often use them to gather evidence of impairment before making a DWI arrest.
However, these tests do not always provide accurate results. Various external factors unrelated to alcohol consumption could influence your performance. Understanding these variables can help you recognize unreliable test results. This could help protect you in court.
Environmental and weather conditions
The location where officers administer these tests matters significantly, and roadside conditions are rarely ideal for accurate assessment. If the ground is uneven or unstable, you might struggle to keep your balance. National Highway Traffic Safety Administration (NHTSA) guidelines generally recommend dry, hard, level and non-slippery surfaces to ensure your safety and the test’s reliability.
Poor lighting during nighttime stops can potentially affect your ability to follow visual cues or maintain focus. Minnesota’s weather may also create challenging conditions for field sobriety tests. Rain, snow and harsh wind could make balance-based tests extremely difficult, even if you are sober.
Physical and medical limitations
Your physical condition might affect test performance. For example, inner ear problems, physical injuries or vertigo may impair your balance regardless of sobriety. In some cases, taking part in field sobriety tests could make your condition flare up. Not only can this be painful, but it may also become more difficult to concentrate.
Psychological and situational stress
Anxiety and nervousness are natural responses to police encounters. These emotions can interfere with your coordination and concentration. Fatigue from a long day at work might also slow your reaction time or ability to think.
Similarly, distractions from passing traffic or the pressure of performing under observation may all contribute to poor test results that have nothing to do with impairment.
Protecting your interests in a traffic stop
In Minnesota, field sobriety tests are not foolproof. It might help to document any relevant physical conditions or roadside conditions in case you need to defend yourself in court. Being aware of the external factors that can affect your results could help you protect yourself from a wrongful charge.
