How Police Misconduct Can Affect a DUI Charge

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Facing a DUI charge can be a scary experience, but the situation becomes even more complicated when police misconduct is involved.

At Arja Shah Law, we specialize in criminal and DUI defense and understand how improper police conduct can significantly impact DUI cases.

Our firm is dedicated to protecting your rights and ensuring that any procedural errors by law enforcement do not go unchallenged. 

This article will cover the following subtopics: 

police misconduct affect dui charge

What Constitutes Police Misconduct in a DUI Case?

Lack of Reasonable Suspicion

Law enforcement officers must have reasonable suspicion to stop a vehicle. This means they must observe specific behaviors or violations that indicate the driver might be impaired.

Any evidence gathered during the stop may be inadmissible in court without reasonable suspicion, as per A.R.S. § 28-1594.

Errors Made Regarding Field Sobriety Tests

Field sobriety tests (FSTs) must be conducted according to standardized procedures.

Errors in administering these tests can lead to inaccurate results.

For instance, uneven surfaces or poor lighting can affect the driver’s performance, making it difficult to determine impairment accurately.

Lack of Probable Cause

After stopping a vehicle, an officer must have probable cause to arrest someone for DUI. This involves observing signs of impairment such as slurred speech, bloodshot eyes, or the smell of alcohol.

Without probable cause, the arrest can be challenged under A.R.S. § 13-3883.

Improper Chemical Testing

Chemical tests (breath, blood, or urine) must be administered correctly to provide accurate results.

Improper calibration of breathalyzers or contamination of blood samples can lead to unreliable evidence.

Any procedural lapses can be grounds for contesting the test results, as outlined in A.R.S. § 28-1323.

Unlawful DUI Arrests

An unlawful arrest occurs if the officer does not follow proper legal procedures. This can include failing to inform the suspect of their rights or conducting a search without a warrant.

Such arrests can violate constitutional protections and result in the exclusion of evidence.

How Can Police Mistakes Influence a DUI Charge?

Police mistakes can significantly impact the outcome of a DUI case.

If it can be shown that the arresting officer violated protocol or the law, the evidence collected may be deemed inadmissible.

For instance, if the stop was made without reasonable suspicion, any subsequent evidence of intoxication could be thrown out, weakening the prosecution’s case. This can lead to charges being reduced or even dismissed.

Police misconduct

Hypothetical Example: Proper vs. Improper Police Conduct in a DUI Arrest

Proper Police Conduct

John is driving home late at night when Officer Smith notices him swerving between lanes. Officer Smith follows proper protocol by observing John’s behavior and notes that erratic driving is a reasonable suspicion for a traffic stop.

After pulling John over, Officer Smith approaches the vehicle and observes signs of impairment, such as bloodshot eyes and the smell of alcohol.

Following standard procedures, he requests John to perform field sobriety tests (FSTs) on a flat, well-lit surface. John fails the tests, and Officer Smith then administers a breathalyzer test, ensuring the device is correctly calibrated. The breathalyzer shows a blood alcohol concentration (BAC) above the legal limit. Officer Smith informs John of his rights and arrests him for DUI.

In this scenario, Officer Smith’s adherence to proper procedures ensures that all evidence collected is admissible in court.

John’s DUI charge is likely to be upheld based on the valid evidence gathered.

Improper Police Conduct

Sarah is driving home late at night when Officer Jones notices her car weaving slightly within the lane.

Without observing more definitive signs of impaired driving, Officer Jones pulls Sarah over, lacking reasonable suspicion. Upon approaching her vehicle, Officer Jones notices a faint smell of alcohol but does not see any other signs of impairment.

He immediately asks Sarah to perform field sobriety tests on a gravel surface with poor lighting, leading to an unfair assessment.

Sarah is invited to take a breathalyzer test, but Officer Jones uses a device that hasn’t been calibrated recently. Despite a borderline BAC reading, Officer Jones arrests Sarah for DUI without clearly informing her of her rights.

In this scenario, Officer Jones’s improper conduct can be challenged in court.

Sarah’s defense attorney can argue that the initial traffic stop lacked reasonable suspicion, the FSTs were conducted under unsuitable conditions, and the breathalyzer test was unreliable.

These factors could lead to the dismissal of the evidence, significantly weakening the prosecution’s case and possibly resulting in the dismissal of Sarah’s DUI charge.

Why the DUI Might Be Dismissed in One Case but Not in the Other

In John’s case, the DUI charge will likely be upheld because Officer Smith followed all proper procedures, ensuring the evidence was collected lawfully and accurately.

There are no grounds to challenge the admissibility of the evidence, making it difficult for John’s defense attorney to argue for dismissal.

Conversely, in Sarah’s case, the DUI charge could be dismissed due to Officer Jones’s failure to follow proper procedures.

The lack of reasonable suspicion for the traffic stop, improper administration of FSTs, and use of an uncalibrated breathalyzer provides multiple grounds for challenging the evidence.

Sarah’s defense attorney can argue that the evidence was obtained unlawfully, leading to its exclusion and potentially the dismissal of the DUI charge.

What Defense Strategies Can You Use Against Police Errors in DUI Cases?

  1. Challenging the Stop: Argue that the officer lacked reasonable suspicion to initiate the traffic stop, suppressing evidence.
  2. Questioning Field Sobriety Tests: Highlight procedural errors or environmental factors that could have affected the FST results.
  3. Disputing Probable Cause: Demonstrate that the officer did not have sufficient probable cause for the DUI arrest.
  4. Contesting Chemical Test Accuracy: Examine the administration and handling of chemical tests to identify errors or contamination.
  5. Arguing Unlawful Arrest: Point out any violations of the suspect’s rights or procedural misconduct during the arrest.

By leveraging these strategies, a skilled DUI defense attorney can effectively challenge the prosecution’s case, potentially leading to reduced charges or dismissal.

Contact Arja Shah Today for DUI Defense

Arja Shah | Shah Law Firm

When facing a DUI charge, the nuances of police conduct can make all the difference.

Our expertise in Arizona DUI laws ensures that your rights are defended and any procedural errors are revealed. 

If you or a loved one is dealing with a DUI charge, contact DUI attorney Arja Shah for a comprehensive and strategic defense.

Contact us today at (602) 560-7408  to schedule a consultation today. 


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