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Apr. 10 2024

Can You Challenge Breathalyzer Results?

Posted By: azhari dev

Getting pulled over for a suspected DUI can be stressful, especially with a breathalyzer test on the line. But the big question is: are breathalyzer results the final say? In Chicago, challenging these tests is a common defense strategy in DUI cases.

With much at stake, including your driving privileges, let’s break down how to dispute a breathalyzer test. We’ll explore successful legal arguments used in the past and what a good

A DUI lawyer in Chicago can help your case.

Can Breathalyzer Results Be Challenged in Court?

DUI can be a hassle experience, especially when a breathalyzer test is administered. These tests are often seen as the ultimate proof of intoxication, but what if they’re not foolproof? In Chicago, challenging breathalyzer results is a common defense strategy employed by DUI lawyers.

Here’s a deeper dive into why and how you might be able to fight a breathalyzer result in court.

Why Fight a Breathalyzer Test?

Breathalyzers, while widely used, are not without flaws. These machines can malfunction or produce inaccurate readings due to various factors. A skilled DUI lawyer in Chicago will explore these vulnerabilities to build a strong defense.

Common Angles of Attack

  1. Calibration Issues: Breathalyzers require regular maintenance and calibration to ensure accuracy. Your attorney will investigate the device’s maintenance records and calibration certificates. If there’s evidence of improper maintenance or outdated calibration, the breathalyzer results could be deemed unreliable.
  2. Procedural Errors: A breathalyzer test is administered according to strict protocol. Deviations from these procedures can cast doubt on the validity of the results. Your lawyer will scrutinize the police report for any procedural mistakes made during the arrest or testing process. Examples of such errors might include improper test administration or failing to wait the required time after consuming certain foods or beverages.
  3. Medical Conditions: Certain medical conditions can interfere with breathalyzer readings, leading to false positives. Your lawyer will explore if any underlying medical issues could have skewed the results.

Strength in Precedent

Chicago courtrooms have seen successful challenges to breathalyzer results in the past. Your lawyer can leverage these precedents by referencing past cases where breathalyzer test results were excluded due to similar issues. This demonstrates to the judge that your case is not isolated and highlights potential weaknesses in the prosecution’s evidence.

The Importance of a Skilled DUI Lawyer

Successfully challenging a breathalyzer result is a complex task that requires a deep understanding of both DUI laws and the science behind breathalyzer testing. An experienced DUI lawyer in Chicago will possess this knowledge and be equipped to:

  • Meticulously examine the details of your case, identifying any potential weaknesses in the breathalyzer test or police procedures.
  • Develop a strategic defense plan tailored to the specific circumstances of your arrest.
  • Effectively argue your case in court, highlighting inconsistencies or errors that undermine the breathalyzer results.

The Potential Benefits of Fighting Back

Mounting a strong defense against a breathalyzer result can significantly impact your case. Depending on the success of your challenge, the following outcomes are possible:

  • Reduced Charges: The prosecution’s case weakens if the breathalyzer results are thrown out. This could reduce charges, such as a lesser offense that carries less severe penalties.
  • Case Dismissal: In the best-case scenario, if your lawyer can successfully demonstrate significant flaws in the breathalyzer test or police procedures, the judge might dismiss the DUI charge altogether.

Facing a DUI charge can feel overwhelming, but remember, you have options. Don’t hesitate to fight for your rights. Consulting with a qualified DUI lawyer in Chicago allows you to explore the possibility of challenging the breathalyzer results and potentially securing a more favorable outcome.

What Are the Potential Errors in Breathalyzer Testing?

Breathalyzers are widely used for DUI enforcement, but they aren’t perfect. Inaccuracies can arise from various factors, creating opportunities for a skilled DUI lawyer in Chicago to challenge the results. Let’s explore some common reasons why breathalyzer tests might be unreliable:

Factors Contributing to Breathalyzer Inaccuracy

How Can Medical Conditions and Substances Interfere with a Breathalyzer Reading?

Breathalyzers are a common tool for DUI enforcement, but they can be susceptible to inaccuracies caused by various medical conditions and substances. Understanding these factors can empower you and your Chicago DUI lawyer to challenge a breathalyzer test.

Factors Causing Breathalyzer Inaccuracy

This bar graph illustrates how certain medical conditions and substances can elevate breathalyzer readings, potentially resulting in false positives.

What is the Rising Blood Alcohol Defense?

There’s a defense strategy you might not be aware of: the rising blood alcohol defense.

Here’s how it works:

Alcohol absorption into your bloodstream takes time. It can continue to rise even after you’ve stopped drinking. This means your Blood Alcohol Concentration (BAC) level at the time of a breathalyzer test might be higher than it was when you were actually driving.

Imagine a cake: It keeps baking even after you take it out of the oven. Similarly, your BAC can keep rising after your last drink.

In Chicago, DUI lawyers often use the rising blood alcohol defense, especially for first-time offenses. Why?

  • Because the timing of the test, relative to your last drink, can mean the difference between a DUI and a DWI (Driving Under the Influence) charge in Illinois.
  • If your BAC was legal while driving but rose above the limit by the time of testing, you might have a strong case.
  • Skilled DUI lawyers will explore the details of your arrest. They might consult experts to explain how alcohol absorption works and how it could have impacted your BAC reading.
  • The goal is to show that the breathalyzer test doesn’t necessarily reflect your level of intoxication at the time you were driving.
  • This defense can be a game-changer. By raising doubt about your actual impairment while driving, your lawyer can potentially weaken the prosecution’s case and influence the verdict in your favor.

Why Is Proper Handling of Breath Samples Critical in DUI Cases?

Facing a DUI charge in Chicago? The way the police handle your breath sample can make or break your case. Here’s why:

  • Chain of Custody Matters: This refers to the documented trail of every person who touches your breath sample, from collection to analysis. It includes dates, times, and the reason for handling.

These strict rules ensure the sample’s authenticity. Any break in the chain raises doubts.
Imagine a document with a flow chart illustrating the chain of custody.

Chain of Custody Flowchart

Note: This general flow may vary slightly depending on procedures.

These strict protocols ensure that your breath sample is the same one analyzed. Any break in this chain, like missing paperwork or an unauthorized person handling the sample, could doubt its validity.

  • Mishandling Leads to Dismissal: If the chain of custody is broken, or there’s evidence of tampering or contamination, your lawyer can argue to exclude the breathalyzer results. Without this key evidence, the prosecution’s case weakens, potentially leading to dismissed charges.
  • Building Your Defense: Your lawyer needs concrete proof to challenge the breath test’s integrity. They’ll look for inconsistencies in the chain of custody records, improper storage, or failure to follow protocol. A skilled lawyer can find these weaknesses and argue for dismissing tainted evidence.
  • The Importance of Details: Proper handling of breath samples is crucial for DUI defense strategies in Chicago. Reliable recordings, airtight procedures, and perfect documentation are essential. Any failures here can be used to overturn your charge.

Attention to detail is paramount in the fight against a DUI charge. Understanding how breathalyzer evidence can be challenged can be a game-changer in your Chicago case, potentially leading to dismissal and saving your license.

Ready to Defend Your Rights? Contact Us Today!

If you’re facing DUI charges in Chicago, don’t wait to seek legal representation. Our experienced DUI defense team at Azhari LLC is here to help you with the legal process and fight for the best possible outcome for your case.

Don’t let a DUI charge frustrate you. Contact us now to schedule a consultation and take the first step towards protecting your rights.


1. Can breathalyzer results be contested in court?

Yes, breathalyzer results can be challenged in court. DUI defense attorneys may question the calibration and maintenance of the breathalyzer device, the qualifications of the operator, and the procedures followed during the test to challenge the results’ validity.

2. What factors can cause inaccuracies in breathalyzer tests?

Breathalyzer test results can be inaccurate due to improper calibration, errors by the operator, or external factors. Chicago DUI attorneys focus on these irregularities, such as the lack of proper calibration maintenance records or procedural mistakes like not following the required observation period before administering the test.

3. How can medical conditions affect breathalyzer results?

Medical conditions such as acid reflux and diabetes, as well as certain diets, can produce falsely high breathalyzer readings. DUI lawyers can use evidence of medical conditions, expert testimony, and scientific data to dispute the results and challenge penalties associated with a DUI.

4. What is the rising blood alcohol defense in DUI cases?

The rising blood alcohol defense argues that a person’s BAC was below the legal limit while driving but rose above it by the time of testing. By presenting experts to explain the timing of alcohol absorption in the body, defense lawyers can create reasonable doubt about the accuracy of the BAC reading at the time of the arrest.

5. Why is the chain of custody important in DUI cases?

Proper handling and chain of custody of breath samples are crucial in DUI cases. Any mishandling, contamination, or deviation from strict protocols can lead to excluding breathalyzer evidence. This can weaken the prosecution’s case, potentially resulting in the dismissal of charges.