Common Mistakes Made During DUI Traffic Stops click for a free consultation

Posted on May 10, 2023 in DUI

Law enforcement officers in Arizona have a duty to abide by the correct procedures and take lawful actions during criminal proceedings, including a traffic stop that is conducted for driving under the influence (DUI). Unfortunately, many police officers break the rules and make mistakes during DUI stops. This can lead to the individual being wrongfully charged with a drunk driving crime.

Lack of Probable Cause for the Traffic Stop

Police officers in Arizona must have probable cause to conduct traffic stops. State law does not permit an officer to pull a motor vehicle driver over only on suspicion of drunk driving. There must be another reason to conduct the stop, such as a violated traffic law. During the stop, the officer may only begin a line of questioning to determine driver intoxication if there is sufficient cause to do so, such as slurred speech or the smell of alcohol. Lack of probable cause for the initial stop or arrest could dismiss the entire case.

Inaccurate Calculation of BAC

In Arizona, a driver is presumed to be drunk if he or she has a blood alcohol concentration (BAC) level at or above 0.08 percent. Law enforcement typically collects this information using a Breathalyzer test, or a device that the driver blows into during the traffic stop to test for alcohol in his or her bloodstream. If the device is not properly maintained or calibrated, however, it can put out inaccurate results. If the police station does not properly maintain its equipment, this could lead to an argument that the evidence is unreliable. 

Incorrect Administration of a Field Sobriety Test

Field sobriety tests are physical tests that are used to determine if a driver is impaired. The three types of field sobriety tests are the one-legged stand, horizontal gaze nystagmus test, and the walk-and-turn test. If a police officer incorrectly orchestrates a field sobriety test or does not properly assess the results, this could lead to inaccurate evidence of driver intoxication that gets thrown out or suppressed during the case.

Failure to Read Your Miranda Rights

Miranda rights, also known as the Miranda warning, is a list of rights that a law enforcement officer is required by the Constitution to read during an arrest. They include the right to remain silent, the right to have an attorney present and the right to have a public defender appointed to you if you cannot afford an attorney. If a police officer makes a DUI arrest without reading the Miranda rights, this is a mistake that could throw out any evidence collected after this failure, including confessions of consuming drugs or alcohol.

Improper Chain of Custody for Evidence

The chain of custody refers to documentation that tracks the movement of evidence through the time it was collected to its containment in a storage facility and any tests that were done on the evidence. Improper chain of custody can rule the evidence as inadmissible in a court of law by compromising its integrity. If multiple individuals handle the evidence – including breath or chemical DUI tests – without proper identification or tracking, this can be used to have the evidence dismissed.

Protect Yourself After a DUI Arrest

If you have been arrested for allegedly driving under the influence in Arizona, contact a DUI defense attorney as soon as possible to represent you and protect your rights. Your lawyer will carefully analyze your case to look for police mistakes that can be used to argue against the DUI charges, bar evidence from being admitted or have the case dismissed. If your attorney finds evidence of law enforcement errors, police misconduct or violations of your civil rights, this could protect you from a DUI conviction. Contact Rosenstein Law Group for a free case consultation if you find yourself in this situation