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When can Illinois police officers lawfully request or require a breath test?

On Behalf of | Feb 13, 2024 | Drunk Driving

Sometimes, drivers immediately understand why a police officer has pulled them over. They may have a burned-out brake light or be aware that their speed is inappropriately high. Other times, they don’t know an officer’s intention for the traffic stop until they approach the vehicle.

Sometimes, an officer might believe that a driver is under the influence of alcohol. A police officer in Illinois might ask someone questions about their activities that day or even ask them to perform field sobriety tests during a traffic stop. Eventually, an officer could request that a driver perform a chemical breath test to determine whether they are over the legal limit for their blood alcohol concentration (BAC) or not. When can police officers in Illinois request or require that a motorist perform a breath test?

When the driver consents

Police officers often get around the limitations on their authority by tricking or manipulating drivers and other members of the public. They ask for permission to do something that otherwise they likely could not. An officer might ask someone to submit to a breath test early in a traffic stop before they have a viable reason to compel them to undergo testing. If a driver gives their consent to testing, an officer could potentially administer it without having the justification to arrest someone or compel them to undergo the test.

When they have probable cause

Police officers begin developing a case against someone as soon as they initiate a traffic stop. They note factors like someone’s appearance and their answer to questions when determining whether they have probable cause to arrest them. What someone says and how they perform on a field sobriety test, combined with their behavior in traffic, might give the officer the probable cause the law requires for them to arrest the driver. Once the officer has the necessary probable cause to arrest someone, they also have the ability to invoke the state’s implied consent law.

If a police officer has the necessary probable cause to arrest someone for impaired driving, the motorist has effectively already given their consent to chemical testing. Should they refuse the test at that point, the officer could arrest them simply because they would not submit to the test. The motorist could then face secondary consequences as their impaired driving case goes through court, and they may also face charges related to the violation of the implied consent law.

Drivers who are aware of their rights and the limits on police authority are less likely to make mistakes that could lead to their prosecution, such as submitting to a test when an officer does not have any real justification to perform it. As such, learning about traffic laws in Illinois may benefit those who regularly drink and worry about facing unfair prosecution.