Top 5 Police Mistakes in A DUI Investigation

CA Vehicle Codes 23152(a)/(b), 23153

Police officers can make mistakes in a DUI investigation which violate the law.    Below is a list of Aizman Law Firm’s top five.

  1. No Reasonable Suspicion For A traffic Stop
  2. Misconduct at Sobriety Checkpoint
  3. Misconduct in Field Sobriety Tests
  4. No Probable Cause For DUI Arrest
  5. Misadministration of Your breath Test

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Common Police Mistakes

     → 1.  No Reasonable Suspicion for a Traffic Stop: You do not need to be pulled over by a police officer specifically on suspicion of driving under the influence in order for you to be arrested for a DUI. As long as the officer has reasonable suspicion that you were committing any traffic violation–from a broken tail light to causing an accident–the traffic stop itself will be legal1. However, if the police officer lacked justification for the traffic stop, any evidence collected after the illegal stop may possibly be suppressed on a motion from your attorney. Since a DUI conviction rests mainly on evidence collected your case may be reduced or dismissed if the stop was egregious.     

 → 2.  Misconduct at Sobriety Checkpoints:  Many DUI arrests that are as a result of a sobriety checkpoint can be challenged if the police officer administering the checks failed to follow the strict rules and guidelines of the checkpoint2  

   → 3.  Misconduct in Field Sobriety Tests:  There are many different kinds of field sobriety tests in California. Each and every one of these tests must be given in accordance with specific NHTSA guidelines.  Many law enforcement officers will not take into consideration fatigue, medical conditions, weather conditions, or the structure of the pavement when giving the tests, as they should. When the officers do not comply with these guidelines this creates an opportunity for your attorney argue that the results of the tests are not reliable.     

 → 4) No Probable Cause for Arrest: After a law enforcement officer conducts a traffic stop for any reason, he must then have probable cause that a crime was committed in order for your arrest to be valid.3 Probable cause means that any reasonable person, or officer in this case, would believe that you were driving under the influence based on the evidence that is presented. If, however, there was no probable cause, your attorney may be able to have all of the evidence from after the arrest suppressed.  There may still be admissible evidence from before your actual arrest but having an unlawful arrest will harm the prosecution’s case immensely.      

→ 5.  Misadministration of Your Breath Test:  If you have been lawfully pulled over and arrested, the arresting officer will administer a breath test in order to check your BAC. California regulations require that the officer continuously observe the driver for 15 minutes before administering the breath test4 . This procedure is to ensure that the driver does not vomit, burp, or otherwise cause alcohol to reappear in the mouth before the breath test and skew the results. It is possible that the officers did not diligently watch the driver for 15 minutes.  They may become distracted with paperwork, setting up the breath test, or talking to other officer’s on-site.  If this happens, your attorney may be able to argue that the procedure was not followed properly and get the results of the breath test suppressed.

Frequently Asked Questions

What are common actions that can be used as probable cause that I was driving under the influence?

Probable cause can include many different actions or symptoms by the driver.  Some of the most common include: slurred speech, flushed face, red or glassy eyes, inappropriate or combative attitude, fumbling when reaching for your license, and general disorientation.

Do the police have to read me my rights when they arrest me?

A common misconception is that a police officer must read you the Miranda rights after you are arrested. However, it is important to remember that the officer must only read you your rights if you are both

(1) placed under arrest, and

(2) the officer continues to interrogate you. If the officer asks no further questions after your arrest, you have not been interrogated and are not entitled to have your rights read. 

If an officer writes a poor report, is that considered a mistake?

Law enforcement officers are required to write up a detailed account of the timeline and events of your arrest. Sometimes, these reports are less than accurate if written anywhere between hours and days after your arrest. Depending on what type of mistake is made in the report will determine if it is relevant to a case. For example, if an officer were to copy/paste portions of a report from a different persons report with incorrect names that could potentially make a significant difference in a case including the DMV hearing.

Hiring A DUI Attorney

Police officers are not infallible. In fact, case records are filled with countless examples of officers who cut corners, make rash decisions, and commit oversights which violate citizen rights. That is certainly true in the context of California DUI arrests. Using a law enforcement officer’s mistakes during their DUI investigation against them can be an effective defense to avoid DUI conviction. It is possible to use these mistakes either to get the charges completely dismissed or to challenge the officer’s legal approach to the arrest and build a strong defense that may encourage the prosecution to reduce your charges. There are many potential mistakes that a police officer can make.

Law enforcement officers are required to follow certain protocols for a DUI arrest to be legal.  It is important to try to remember the details of your arrest and share them with your attorney because it is possible that that the arresting police officer did not follow protocol or pulled you over without sufficient probable cause.  At the Aizman Law Firm, our experienced DUI attorneys can help you with questions you might have about the entire DUI process and what you can expect.

If you would like to have a free confidential consultation about your case, please call our office at: (818) 351-9555.

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  1. Terry v. Ohio, 392 U.S. 1 (1968 []
  2. Cal. Veh. Code §2814.2(a []
  3. Carroll v. U.S., 267 U.S. 132 (1925 []
  4. Cal. Code of Reg., Title 17 §1219.3 []

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