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5 Common Police Mistakes During a DUI Arrest


If you have been arrested for an OWI, this doesn’t mean that you are guilty of the crime. Police are required to follow strict protocol in order to initiate a traffic stop and make an arrest. If an officer makes a mistake at any phase of an OWI investigation, your criminal defense attorney could file a motion to suppress, which could make any evidence collected at the scene inadmissible in court. Without any evidence against you, the judge may dismiss your entire case.

The following are the most common mistakes made by law enforcement during an OWI investigation:

  • No reasonable suspicion or probable cause - A police officer needs to have reasonable suspicion to make a traffic stop. This often comes in the form of a traffic violation, including speeding, reckless driving, switching lanes without using your turn signals, or driving with a broken taillight. Furthermore, police can conduct a traffic stop in the event of an emergency, such as being pulled over on the side of the freeway. Law enforcement must also establish probable cause before making an arrest, essentially meaning there is evidence to back up an officer’s claim or suspicion that you were drunk driving. Evidence of intoxication includes the smell of alcohol on your breath, slurred speech, red eyes, open container in your car, or your results from the breathalyzer and field sobriety test. If the arresting officer had no valid reason for making a traffic stop or no probable cause, your case can be dismissed.
  • Illegal search and seizure - Not only does an officer need probable cause to make an arrest, but also to search your vehicle. While you need a search warrant to search a home or body, motor vehicle searches are typically an exception to the warrant requirement. In order to conduct a search, police need to have one of those two things before they can conduct a search. If law enforcement failed to establish probable cause prior to a search, anything the officer finds during the illegal search can be suppressed in court.
  • Improper field sobriety testing - Field sobriety testings (FSTs) (i.e. walk and turn, horizontal gaze nystagmus, and one-legged stand) must be administered according to standards approved by the National Highway Traffic Safety Administration (NHTSA). An officer must take your medical conditions and the road conditions into consideration, as well as report the results of each test in detail. Failure to follow the proper steps means the test results cannot be used in court.
  • Improper breath testing - A police officer who administers the breath test needs to be certified and trained. Not only does the arresting officer need to observe you for 20 minutes, but also ensure the testing device is properly calibrated. If a test isn’t performed correctly, it can be beneficial for your case.
  • Fail to read your Miranda rights - You’re probably familiar with the phrase, “You have the right to remain silent.” If you are in police custody and question you about anything besides your basic identifying information without reading your Miranda rights, anything you say when you were questioned cannot be used against you in court. On the other hand, if the arresting officer does read you your Miranda rights, avoid speaking until you have an attorney present.

Charged with an OWI in Milwaukee? Request a free consultation with our experienced criminal defense lawyer at the Law Offices of Christopher J. Cherella today.

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