Top

Common Police Errors in a DUI Investigation

During a DUI investigation, police officers are required to follow strict protocols to protect the rights of the suspect, ensure the evidence is lawfully collected, and provide fairness and transparency to the suspect.

However, there are many occasions where law enforcement authorities disobey these rules, typically by mistake. If an officer commits an error during a DUI arrest, a criminal defense lawyer can file a motion to suppress evidence on behalf of the defendant.

If the judge believes the evidence was illegally obtained, then it will be inadmissible in court. In many cases, without key evidence to support the prosecution’s case, the defendant’s charges will be dismissed.

The following are the most common police errors in a DUI investigation:

  • The police failed to establish “reasonable suspicion” – If the police do not have a reason to pull you over, it is considered an illegal traffic stop. An officer must establish reasonable suspicion to make a traffic stop, meaning you either committed a traffic violation (i.e. reckless driving, speeding, or driving with a busted taillight) or pulled over on a busy freeway and appear in need of help. Without establishing reasonable suspicion, any evidence gathered will be thrown out at trial.
  • The police failed to establish “probable cause” – To make a lawful arrest, police must have enough evidence that any reasonable person believes a crime has been committed. Without probable cause, any evidence obtained after the arrest cannot be used in court.
  • The police improperly administered a field sobriety test – The NHTSA created rules police officers must follow when administering a field sobriety test, such as clearly explaining each test, ensure the test is performed on level ground, and account other factors that may influence the results like age, health conditions, and fatigue. Failure to properly administer these tests means the results are inadmissible in court.
  • The police improperly administered a breath test – Police officers use breathalyzers to determine a suspect’s blood alcohol content. However, these devices must be properly calibrated before use. In addition, law enforcement must conduct a 15-minute observation period to ensure the suspect doesn’t vomit, burp, or consume anything since it will affect the test results. If an officer makes a mistake when administering a breath test, the results cannot be used as evidence.

If you have been arrested for DUI in Santa Rosa, contact the Law Offices of Evan E. Zelig, P.C. and schedule a free consultation today.