Breath Test Evidence in Massachusetts Drunk Driving (OUI) Cases: A Comprehensive Guide

Breath Test Evidence in Massachusetts Drunk Driving (OUI) Cases: A Comprehensive Guide

(and finding a lawyer who actually knows how to get them OUT!)

Yesterday on Friday, 17 October 2025, SUPPRESSED: In Commonwealth of Massachusetts v. Defendant, Docket No.  2567 CR 0666, our Motion in Limine to exclude breath test results was ALLOWED. Our client’s Breath Test Results of .16 are suppressed and inadmissible against him at trial.*

If you have been accused of OUI (Operating Under the Influence, DUI: Driving Under the Influence or DWI: Driving While Intoxicated, synonymous acronyms for the same crime know colloquially as “drunk driving”) and have taken the breath test (Breathalyzer) you must hire a lawyer with a thorough understanding of the Dräger Alcotest 9510, the requirements for admissibility of breath tests taken by this machine, and how to attempt to Suppress these results pursuant to Massachusetts General Law, Chapter 90, §24k, 501 Code Mass. Regs. §2.55. and Com. v. Pierre, 72 Mass.App.Ct. 230, 890 N.E.2d 152 (2008).

If you’re facing a drunk driving charge in Massachusetts, understanding the role of breath test evidence is crucial. Breathalyzer results are a key component of many OUI cases, but they’re not infallible. In this article, we’ll explore the intricacies of breath test evidence in Massachusetts OUI cases, helping you navigate the complexities of the law.

 

In this Blog OUI (Operating Under the Influence) and DUI (Driving Under the Influence) or DWI (Driving While Intoxicated) will be used interchangeably as synonymous acronyms for the same crime know colloquially as “drunk driving”. However, in Massachusetts the crime is referred to as Operating Under the Influence (OUI).

 

How Breath Tests Work in DWI Cases

Breathalyzers measure the concentration of alcohol in a person’s breath to determine their blood alcohol content (BAC). In Massachusetts, a BAC of 0.08% or higher is considered impaired. However, breath tests are not foolproof and can be subject to various errors.

 

Challenging Breath Test Evidence in a DUI

There are several ways to challenge breath test evidence in Massachusetts OUI cases:

  • Breath Test Machine Malfunction

    : Breathalyzers must be properly calibrated and maintained. If the machine is faulty or not functioning correctly, the results may be unreliable.

  • Operator Error when administering the Breath Test

    : The officer administering the test must follow strict protocols. Any deviation from these protocols can compromise the accuracy of the results.

  • Breath Test Mouth Alcohol

    : The presence of mouth alcohol, such as from recent consumption or dental issues, can skew the results.

  • Medical Conditions

    : Certain medical conditions, like acid reflux or diabetes, can affect the accuracy of breath test results.

Defending Against Breath Test Evidence in your Drunk Driving Case

If you’re facing an OUI charge based on breath test evidence, it’s essential to work with an experienced criminal defense attorney who can:

  • Review the Breath Test Results

    : Carefully examine the breath test results to identify any potential errors or inconsistencies.

  • Challenge the Breath Test’s Accuracy

    : Investigate the maintenance and calibration records of the breathalyzer machine.

  • Question the Officer’s Protocol when Operating the Dräger Alcotest 9510

    : Determine if the officer followed proper procedures when administering the test.

Conclusion
Breath test evidence is a critical component of many OUI cases in Massachusetts. However, it’s not a guarantee of guilt. By understanding the limitations and potential errors of breath tests, you can build a stronger defense. If you’re facing an OUI charge, consult with a skilled criminal defense attorney who can help you navigate the complexities of the law.

 

I have been providing Operating Under the Influence (OUI and OUI Drugs, DUI and DWI) defense services in Massachusetts for over Thirty (30) years.  I have been named a “Superior DUI Attorney” by the National Advocacy for DUI Defense, one of the “Ten best attorneys for Massachusetts”, by the American institute of DUI/DWI attorneys, a “Top 100 Trial Lawyer” by The National Trial Lawyers, I have earned the “Clients’ Choice Award” by AVVO, the Client Champion Platinum Award by Martindale-Hubbell and I have won over Ninety Percent (90%) of my trials.*

Call a Top 10 Massachusetts OUI Attorney Now at: (508) 393-4162.

This blog is not intended to be legal advice, if you have been charged with Operating Under the Influence (OUI, DUI, DWI all common acronyms varying by state for “Drunk Driving”) or any other crime in Massachusetts you should call an experienced and successful Drunk Driving lawyer immediately.