Evidence in a DUI Case

Evidence in a DUI case can include officer testimony, a chemical test, video footage, physical evidence, and more. All kinds of evidence can be challenged by a DUI lawyer.

In California, every DUI case is decided based on the weight of the evidence. Many defendants think the evidence against them is overwhelming, but in reality, DUI evidence is often flimsy. The prosecution has to prove beyond a reasonable doubt that you were either over the legal limit of intoxicants in your system, were impaired by those intoxicants, or both. This is hard to do, and the prosecutor has limited evidence to work on.

The types of evidence used against you in your DUI case may include:

  • Officer testimony. The arresting officer will almost always be called to testify at trial. They may claim that you slurred your words, stumbled when you walked, smelled of alcohol or drugs, or failed a field sobriety test.
  • Eyewitness testimony. Witnesses are most common when there was an accident. Others at the scene may have observed you driving dangerously observed seemingly intoxicated behavior after the accident.
  • Police reports. Police fill out reports for every arrest. Since these reports are written within hours of the incident, they are considered to have crucial details that could be forgotten later.
  • Video footage. Video footage may be used if the arrest was caught on a police patrol camera, a nearby security camera, or a witness’s cell phone. This footage is often used to show the jury that you stumbled or slurred your words as the officer said.
  • Statements you made during your arrests. If you admitted you had been drinking or using drugs, this statement will be used against you—even if you didn’t sign a formal confession.
  • Physical evidence. In some cases the police will recover physical evidence by searching your car. The most common evidence is either open containers of alcohol in the vehicle, or drug paraphernalia.
  • Forensic evidence. If your case involves an accident, a police investigator may have gathered evidence about how fast you were traveling or whether you tried to hit the brakes.
  • Chemical test. By far the most common evidence in a DUI case is a breath test, blood test or urine test that attempts to determine what amount of alcohol or drugs were in your system.

How a DUI Lawyer Fights the Evidence against You

The prosecution will attempt to draw on as many different forms of evidence as possible. But all of the different types of evidence above are flawed in some way. A DUI lawyer knows how to fight each one. For example:

  • Officer testimony. Officer testimony is often simply wrong. Your lawyer will probe the officer in advance by summoning them as a witness for your DMV hearing. This gives you a chance to see if their story has errors compared to the earlier police report—or if they change their story in court.
  • Eyewitness testimony. Witnesses often have a limited perspective. Many don’t remember things clearly and will make mistakes when your lawyer cross examines them.
  • Police reports. Police reports are often hastily written and may contain outright inaccuracies.
  • Video footage. Video footage is a double-edged sword. Often, the video actually shows that you did not stumble or slur your words as the officer indicated. Your lawyer will look for any video footage that may exonerate you.
  • Statements you made during your arrests. If you weren’t properly advised of your rights, the statements you made may not be admissible in court.
  • Physical evidence. Having bottles or drug paraphernalia in your car does not mean you driving under the influence. On their own they may justify only an open container or drug possession charge,
  • Forensic evidence. There are many explanations for why you may have been speeding or didn’t stop in time. Forensic evidence rarely carries a DUI case on its own.
  • Chemical test. This is the evidence that seems most incriminating, but it’s often the flimsiest. All chemical tests are subject to error. Your lawyer will pull data on the tests to see if the testing device or laboratory procedure was flawed. Chemical test evidence can also be disputed on the grounds of rising BAC, mouth alcohol, diet and other factors.

You should never assume you will be proven guilty until you speak to a good DUI defense lawyer. Your lawyer may be able to help you overturn the most serious evidence against you, and potentially win your case.

Have you been charged with DUI? We can connect you with an experienced Los Angeles DUI lawyer and get you a FREE consultation. Fill out the form to the right or call (310) 862-0199 and get your free consultation today.

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