Breath Test Results Thrown Out in Massachusetts: What the Hallinan Decision Means for OUI Defendants

Last week, the Massachusetts Supreme Judicial Court issued a major ruling in Commonwealth v. Hallinan, 491 Mass. 730 (2023), reaffirming what defense attorneys have known for years: the state’s breathalyzer program was a mess, and the evidence it produced can’t be trusted. The decision formally excludes breath test results from a critical time period—June 2011 through April 18, 2019—unless the Commonwealth can prove their reliability in each individual case.

As a criminal defense attorney, I’ve seen firsthand how breath test results are often treated as ironclad evidence in OUI prosecutions. The Hallinan decision is a long-overdue recognition that science without transparency isn’t justice—it’s just conviction by shortcut.

What Did the SJC Decide?

The Court upheld a lower court finding that the Office of Alcohol Testing (OAT) failed in its obligations to ensure the scientific integrity of breathalyzer machines. Specifically, OAT withheld evidence, failed to disclose critical information about calibration practices, and essentially misled courts and defense counsel for years. The SJC ruled that breath test results from the Alcotest 9510 device during the affected time period are presumptively inadmissible unless the state can meet a high burden to prove reliability.

Who Is Affected?

If you’re facing an OUI charge based on a breath test between June 2011 and April 18, 2019, your defense just gained significant leverage. Prosecutors may now be forced to drop breathalyzer evidence entirely—or prove in court why your specific test should be admissible.

For people who already pled guilty or were convicted during that period, Hallinan could also open the door to post-conviction relief. If your case depended on a breath test, it’s worth revisiting whether that conviction was built on unreliable evidence.

Why It Matters

Hallinan isn’t just about faulty machines—it’s about accountability. When the government presents scientific evidence in court, it has a duty to ensure that evidence is accurate, fair, and disclosed fully to the defense. The misconduct by the Office of Alcohol Testing violated that duty, and the SJC’s decision reflects the seriousness of that breach.

This case should serve as a warning: justice can’t be automated. Breath tests may seem like simple numbers, but behind those numbers is a system that depends on honesty, oversight, and due process. When that system fails, people’s lives are unfairly upended. I’m glad the SJC stepped in—and I’ll continue fighting to make sure my clients are judged by facts, not faulty machines.

What Is Discovery in a Criminal Case in Massachusetts?

In every Massachusetts criminal case, the defense has the right to receive discovery—copies of the evidence the prosecution plans to use.

This can include:
- Police reports 
- Surveillance video 
- 911 calls 
- Witness statements 
- Forensic results like fingerprints or DNA

Discovery is governed by Rule 14 of the Massachusetts Rules of Criminal Procedure. In most cases, the Commonwealth must turn over basic materials within a set timeline after arraignment. But not everything is automatic—sometimes you have to file a motion to get specific items.

I often see discovery come in late, incomplete, or missing key records. That’s why I push aggressively for full disclosure. If the government delays or fails to provide evidence, we can file a motion to compel—and in some cases, exclude the evidence altogether.

Understanding what’s in discovery (and what’s not) can make or break a defense. I don’t just wait for the file—I go after what matters.

What Is a No Trespass Order in Massachusetts?

A no trespass order is a written notice that tells someone they’re no longer allowed on a particular piece of private property. In Massachusetts, these are most commonly issued by businesses, landlords, or homeowners—and they don’t require a court order to be valid.

Police often serve these notices, but they’re not criminal charges themselves. That said, if you ignore the order and return to the property, you can be charged with trespassing under G.L. c. 266, § 120. The penalties include a fine or even jail time, especially if it’s part of a larger dispute.

No trespass orders are frequently used in shoplifting or disturbance cases. I’ve seen clients issued one after being accused of minor conduct in a store or an apartment complex. Even if no charges are filed at the time, the order stays in place—and violating it later can lead to a court date.

It’s important to take these notices seriously. If you’ve been given one and you think it was unfair—or if you're now facing charges for allegedly violating it—I can help you understand your options and defend your case.

Can the Police Search Your Car Without a Warrant in Massachusetts?

In Massachusetts, police don’t always need a warrant to search your car. But that doesn’t mean they can search it for no reason.

Warrantless car searches are allowed under several exceptions:
- If the officer has probable cause to believe there’s evidence of a crime
- If you give consent
- If the item is in plain view
- If the car is being towed or impounded

The most common justification is probable cause—like if the officer smells marijuana, sees a weapon, or gets conflicting statements. But officers sometimes stretch the truth or claim consent when none was given.

If your rights were violated during a search, I can file a motion to suppress the evidence. I’ve won cases where drugs, weapons, or other items were thrown out because the search was illegal.

You don’t have to let police search your car—and saying “no” doesn’t mean you’re guilty. If your car was searched and charges followed, let’s talk.

What Is the Difference Between Sealing and Expunging a Record in Massachusetts?

If you have a criminal record in Massachusetts, you may have heard about sealing or expungement. They sound similar—but they’re not the same.

Sealing means your record still exists, but it’s hidden from most employers, landlords, and the general public. Law enforcement and certain government agencies can still access it. Sealing is available in more cases and is often quicker to obtain.

Expungement means the record is completely erased—as if it never happened. But it’s only available in limited circumstances, like identity theft, clerical errors, or certain juvenile cases.

Both options require a petition, and some cases may involve a court hearing. I help clients evaluate which path is available and makes the most sense based on their record, goals, and eligibility.

If your past is holding you back, there may be a legal way to move on from it. I can help you figure it out.