Can a DUI Charge Be Dismissed for an Improper Traffic Stop?
Nov. 5, 2025
When a person gets stopped by law enforcement and charged with DUI, it can feel like the situation is out of their control.
However, certain legal defenses can be raised, particularly if there were issues with how the traffic stop was conducted.
An experienced Brentwood DUI lawyer will understand the emotional strain a charge can create and strive to provide guidance and advocacy that can make a meaningful difference. If you’re dealing with a DUI charge and suspect the traffic stop may have been improper, reach out to William L. Pomeroy Law to discuss your options.
Legal Basis for Challenging a Traffic Stop
A traffic stop is a seizure under the Fourth Amendment, meaning law enforcement must have a legitimate reason to pull a driver over. If the stop lacked probable cause or reasonable suspicion, any evidence obtained afterward, including DUI test results, may be challenged in court.
For example, an officer cannot stop a vehicle without observing some type of traffic violation or behavior suggesting a violation has occurred. Challenging the legality of a traffic stop is often a critical first step in fighting a DUI charge.
Indicators of an Improper Traffic Stop
Not every traffic stop is automatically improper, but there are specific signs that the stop may have violated constitutional rights. Recognizing these indicators can help a DUI defense:
Lack of reasonable suspicion: Officers must observe a clear traffic violation or behavior that justifies the stop. If they pull a driver over for no apparent reason, the stop may be invalid.
Pretext stops: If the primary motivation for a stop was unrelated to traffic enforcement and aimed solely at investigating suspected DUI, this may be grounds for dismissal.
Discriminatory stops: Stops based on race, gender, or other protected characteristics violate constitutional rights.
Failure to follow protocol: Officers are required to adhere to specific procedures during a traffic stop. Deviations from protocol can undermine the legitimacy of the stop.
If any of these indicators are present, it may open the door for a legal challenge that could result in a DUI charge being dismissed.
The Exclusionary Rule and DUI Evidence
One of the most powerful tools in a DUI defense is the exclusionary rule. This legal principle prevents evidence obtained through unconstitutional means, such as an improper traffic stop, from being used in court.
When evidence is suppressed under the exclusionary rule, it can dramatically weaken the prosecution’s case. For example, if a breathalyzer or field sobriety test was administered after an unlawful stop, the results might be inadmissible. While this doesn’t automatically guarantee a dismissal, it often puts the prosecution in a much tougher position.
Common Defenses Related to Traffic Stops
An experienced attorney can evaluate the specifics of a traffic stop and determine if any defenses apply. In DUI cases, defenses related to the stop itself are often among the most effective:
No probable cause: Arguing that the officer lacked a legitimate reason to initiate the stop
Illegal detention: Challenging the length or conditions of the stop if the officer exceeded reasonable limits
Improper field sobriety testing: Highlighting errors in how tests were administered that may invalidate results
Faulty equipment: Questioning the accuracy or calibration of breathalyzers or other testing devices
These defenses can form the basis for filing motions to suppress evidence, which can lead to dismissal or reduced charges.
How Evidence Suppression Works
Evidence suppression isn’t automatic. It requires filing specific motions in court, and the judge will hold hearings to examine whether the stop was lawful. Here's a breakdown of the process:
Filing a motion to suppress: The defense submits a formal request asking the court to exclude evidence obtained during the traffic stop.
Pre-trial hearing: Both the prosecution and defense present arguments. The judge evaluates whether the stop violated the Fourth Amendment.
Ruling: If the judge rules the stop was improper, the related evidence is suppressed. This can significantly affect the DUI case.
This process requires careful attention to detail and knowledge of procedural law, which is why working with an experienced attorney is crucial.
Factors Courts Consider in Traffic Stop Challenges
Courts consider multiple factors when evaluating claims of an improper traffic stop:
Officer observations: Did the officer witness any traffic violation or suspicious behavior?
Duration and scope of stop: Was the driver detained for longer than necessary?
Driver’s behavior: Did the driver comply with instructions and act reasonably during the stop?
Documentation: Did the officer document the stop accurately and follow standard protocols?
Courts weigh these factors to determine whether the Fourth Amendment was violated. Even minor procedural errors can sometimes provide grounds for suppressing evidence in DUI cases.
Importance of Early Legal Intervention
When facing a DUI charge, timing matters. The sooner a person consults with an attorney, the more effective the defense can be. Early intervention allows for:
Evidence review: Assessing police reports, dashcam footage, and officer notes for inconsistencies
Witness statements: Gathering statements from passengers or bystanders while memories are fresh
Investigation: Analyzing the circumstances surrounding the traffic stop and testing procedures
Prompt legal action helps preserve rights and increases the chances of challenging evidence successfully.
DUI Consequences and Risks
DUI charges carry serious consequences, even if they’re first offenses. Beyond fines and potential jail time, a DUI conviction can affect:
Driving privileges: License suspension or revocation
Employment: Certain jobs may be lost or opportunities denied due to a criminal record
Insurance: Increased premiums or policy cancellation
Personal reputation: The social and emotional impact of a DUI charge can be lasting
Given these risks, a strong legal defense can make a substantial difference in protecting a person’s future.
Key Strategies an Attorney May Use
When challenging a DUI stemming from an improper traffic stop, attorneys may deploy a combination of strategies:
Examine police procedures: Reviewing whether officers followed standard protocols
Scrutinize traffic violations: Determining if there was a legitimate reason for the stop
Question testing methods: Identifying flaws in field sobriety tests or breathalyzer administration
Negotiate with prosecutors: Seeking reduced charges or alternative resolutions if evidence is weak
While every case is unique, these approaches can be powerful tools for defending clients against DUI charges.
Scenarios Where DUI Charges May Be Dismissed
Though not guaranteed, there are specific scenarios where a DUI charge may be dismissed due to an improper traffic stop:
Unlawful stop without probable cause: No observed traffic violation or behavior to justify the stop
Evidence obtained illegally: Breathalyzer or blood tests conducted without proper authority
Officer misconduct: Actions that violate constitutional rights, such as discriminatory stops
Procedural errors: Failure to follow legal requirements for detention or testing
Each scenario requires careful legal analysis to determine whether dismissal is viable.
Defend Yourself Against DUI Charges
If you’ve been charged with a DUI and believe the traffic stop was improper, consulting with your criminal defense attorney as soon as possible is critical. William L. Pomeroy provides dedicated support to clients in Davidson County, Williamson County, and Rutherford County. Their experience and focus on defending client rights make them a valuable ally in challenging DUI charges.
Facing a DUI doesn’t have to be the end of the road. With the right guidance, you can protect your rights and work toward the best possible outcome. Reach out to William L. Pomeroy Law to schedule a consultation and explore the possibility of having a DUI charge dismissed due to an improper traffic stop.