How Can You Challenge the Accuracy of Breath Testing in DWI Cases?
In many DWI cases, it's common to assume that a breath test is automatically accurate. However, there are situations where the test results may not accurately reflect the truth. Challenging these results can make a significant difference in your case, and having the proper guidance can help you feel more confident in taking action.
At The Law Office of Justin K. Hall P.C., I help my clients question and challenge breath testing procedures when appropriate, advocating for their rights in DWI cases. Located in Rockwall, Texas, I serve clients throughout Dallas County, Collin County, Hunt County, and Kaufman County.
Working with an experienced DWI attorney can provide the support and direction you need to address concerns about breath test accuracy. Contact me today to discuss your situation and explore your options.
How Breath Testing Works in DWI Cases
Breath testing is one of the most common methods used by law enforcement to estimate a driver's blood alcohol concentration (BAC). Devices like breathalyzers measure the amount of alcohol in a person’s breath and provide a reading that’s used as evidence in court. While these machines are widely used, they aren’t infallible, and the results can be affected by a variety of factors.
Breath testing relies on assumptions about how the body absorbs and eliminates alcohol. The test estimates a driver's BAC based on the alcohol in their breath, not directly in the bloodstream. This process can introduce variability, allowing readings to differ from a person’s actual blood alcohol content.
Common Errors in Breath Tests
Breath tests can be affected by both human and mechanical factors. Recognizing these potential sources of error can help you and your DWI attorney identify ways to challenge the accuracy of the test. Some common sources of breath test errors include:
Calibration errors: Breath test devices must be regularly calibrated to maintain accuracy. Improper or outdated calibration can produce inaccurate results.
Mouth alcohol: Residual alcohol in the mouth from recent drinking, dental products, or certain medical conditions can inflate readings.
Medical conditions: Some conditions, such as acid reflux, diabetes, or gastrointestinal issues, can affect the test results.
Environmental factors: Factors, such as temperature, humidity, and the presence of certain chemicals, can interfere with breathalyzer sensors.
Operator error: Mistakes made by the officer administering the test or recording the results can also impact accuracy.
Even minor errors in these areas can result in readings that are higher or lower than a driver’s actual BAC. Identifying these issues is key when working with an experienced DWI attorney to build a defense.
How to Challenge Breath Testing in Court
Challenging the accuracy of a breath test often involves presenting evidence that shows the results may not be reliable. While each case is unique, there are several approaches that you may be able to use. These strategies often require the assistance of an attorney who understands the nuances of DWI law and the technical aspects of breath testing.
Review the Device Maintenance Records
One of the first steps in challenging a breath test is to examine the maintenance and calibration records of the device used. These records can show whether the device was properly maintained and regularly checked for accuracy.
Check calibration logs: Verify that the breathalyzer was calibrated according to the manufacturer’s schedule.
Inspect service records: Look for documentation of maintenance, repairs, or malfunctions.
Assess device age: Older devices may be more prone to inaccuracies and mechanical failures.
By reviewing these records, a DWI attorney can determine whether the device used in your case met required standards and whether its readings can be trusted.
Review the Device Certification
Breathalyzers must be certified by the state or meet approved standards. If certification is outdated or missing, results may be inadmissible.
Check device approval: Confirm the breathalyzer model was approved for use in Texas at the time of testing.
Review operator credentials: Law enforcement officers must be trained and certified to administer tests accurately and effectively.
Investigate record-keeping: Proper documentation of test administration is required to ensure evidence holds up in court.
Establish the Chain of Custody
Proper handling and storage of breath test results is essential. If records are incomplete or tampered with, the credibility of the results can be called into question.
Document handling procedures: Review how the test results were collected, stored, and transmitted.
Identify discrepancies: Any missing signatures, dates, or procedural steps can weaken the prosecution’s case.
Confirm test timing: The timing between tests and arrest may affect accuracy, particularly if delays occur.
Challenging these technical aspects requires careful analysis, which a DWI attorney can provide to support a strong defense.
Identify Potential Human Errors
Human error can significantly impact the accuracy of breath tests. Police officers and technicians must follow strict protocols when administering tests, and any deviation from these protocols can establish grounds for challenging the results.
Improper testing procedures: Failing to follow step-by-step procedures can lead to inaccurate results.
Incorrect documentation: Errors in recording test times, results, or other relevant data may affect admissibility.
Inadequate observation: Officers must observe subjects for a specific period to prevent mouth alcohol contamination.
Highlighting these errors with the help of a DWI attorney can cast doubt on the reliability of the breath test.
Consider Medical Conditions and Medications
Certain medical conditions or medications can interfere with breath testing. For example, medical conditions that cause regurgitation or hyperventilation can potentially elevate breath alcohol readings. Some conditions to consider include:
Gastrointestinal issues: Acid reflux or vomiting shortly before the test can affect the device's readings.
Diabetes: Certain metabolic conditions can produce chemical compounds in the breath that mimic the scent of alcohol.
Medications: Mouth rinses, inhalers, or other drugs may impact sensor readings.
Providing thorough medical evidence can help you strengthen your challenge to the breath test results in court.
Alternative Evidence to Support Your Case
In addition to questioning the breath test, submitting other types of evidence may help your defense. Collecting and presenting this information can provide context and challenge assumptions about intoxication. Some key types of alternative evidence that you should consider include the following.
Blood tests: Blood draws are generally more accurate than breath tests and can serve as a counterpoint.
Field sobriety test results: Observations from standardized field tests may show inconsistencies with BAC readings.
Witness testimony: Accounts from passengers, coworkers, or others may provide insight into your behavior and level of impairment.
Surveillance or video evidence: Video footage can reveal behavior that contradicts the breath test results.
Using alternative evidence in combination with breath test challenges can strengthen your defense and provide a more comprehensive view of your situation.
Common Mistakes When Challenging a Breath Test in Texas
In many DWI cases, drivers may attempt to challenge breath tests on their own. However, doing so can often lead to mistakes that could weaken your case. Understanding these pitfalls can help you and your DWI attorney build a stronger strategy. Some common mistakes to avoid include:
Relying solely on device inaccuracies: While device errors are important, ignoring other evidence may limit your defense.
Missing deadlines: Legal motions and evidence requests have strict timelines that must be met.
Failing to document medical conditions: Without proper medical records, claims about interference may be dismissed.
Underestimating procedural errors: Small deviations in testing protocols can be critical and should be highlighted.
By avoiding these mistakes, you increase the chances of effectively challenging breath test results. Your DWI attorney can guide you through the process and help identify all relevant issues.
Reach Out to an Experienced Lawyer
Being charged with a DWI following a breath test can be a challenging experience. However, there are avenues available for challenging breath test results in court. At The Law Office of Justin K. Hall P.C., I’ve helped clients question and challenge breath testing results and procedures.
If you’re facing a DWI charge or have concerns about test accuracy, I can help as your dedicated DWI attorney, providing clear guidance and representation throughout the legal process. Located in Rockwall, Texas, I serve clients throughout Dallas County, Collin County, Hunt County, and Kaufman County. Reach out to me today to schedule a consultation and discuss your case.