Commonwealth v. Hallinan and Massachusetts Alcotest 9510 Cases

For years, Massachusetts police departments used the Draeger Alcotest 9510 breathalyzer to generate blood alcohol concentration evidence in OUI cases. Misconduct later discovered in the state testing program now affects past dispositions, current prosecutions, and future trials or retrials involving those results. A reported breathalyzer number often influenced whether a defendant pleaded guilty, admitted to sufficient facts, or went to trial, and it could become the Commonwealth’s most important trial evidence. The reliability of that number depended in part on how the Office of Alcohol Testing calibrated and certified the device.

During consolidated litigation, a District Court judge ordered the Massachusetts Office of Alcohol Testing to produce the records used to calibrate and certify the Alcotest 9510 devices. The Office produced 1,976 worksheets and represented that the production was complete. It had intentionally withheld another 432 worksheets reporting failures in the annual calibration process. The undisclosed records prevented defendants, prosecutors, and judges from evaluating the testing program on a complete record and created a statewide due process problem.

The Supreme Judicial Court responded in Commonwealth v. Hallinan, 491 Mass. 730 (2023). The decision affects three groups. A defendant in a past case may use Hallinan to support a Rule 30 motion to withdraw a guilty plea or admission to sufficient facts, or to set aside a conviction after trial. In a current prosecution, an affected result must be excluded. At any future trial or retrial of an affected case, the Commonwealth may not use that result.

The rule does not apply to every OUI case or every breathalyzer result. The amended opinion applies when the case included a breath test performed on an Alcotest 9510 device last calibrated and certified before April 18, 2019. The device’s calibration and certification history controls, not the date on which the defendant submitted to the breath test. The decision gives an affected defendant a conclusive presumption of egregious government misconduct, but it does not automatically vacate a past disposition or dismiss a pending charge.

A defendant seeking postconviction relief must file an individual Rule 30 motion. The additional showing depends on whether the case ended by plea, admission to sufficient facts, or conviction after trial. This page explains the Ananias litigation, the amended Hallinan rule, what a motion must establish, what an allowed motion changes, and what clients and counsel should collect before seeking relief.

The First Ananias Ruling

In the consolidated litigation known as Ananias, defendants challenged breath-test results from the Draeger Alcotest 9510. The Office of Alcohol Testing (OAT) calibrated and certified the instruments used by Massachusetts police departments. OAT did not formally adopt written protocols to standardize that work until September 2014. Before then, laboratory personnel transmitted procedures informally.

The District Court judge initially determined that OAT’s methodology produced presumptively unreliable results. The judge allowed the defendants’ motion as to results from Alcotest 9510 instruments calibrated and certified between June 1, 2011, and September 14, 2014. Under the first Ananias ruling, the Commonwealth could attempt to prove in an individual case that OAT had calibrated and certified the particular device through scientifically reliable methods.

A later joint stipulation generally ended that case-specific procedure in pending cases. Exceptions applied to motor vehicle homicide by OUI, OUI causing serious bodily injury, manslaughter by motor vehicle, and a fifth or subsequent OUI charge.

The 432 Withheld Calibration Worksheets

The later litigation concerned OAT’s discovery disclosures as well as its laboratory practices. The parties stipulated that the judge had ordered OAT to produce all annual certification and calibration worksheets. OAT produced 1,976 worksheets and represented that the production was complete. OAT had intentionally withheld another 432 worksheets that reported failures in the annual calibration process.

OAT did not tell the prosecutors, defense attorneys, or judge that it had withheld those failed worksheets. The parties stipulated that the documents were exculpatory. The judge therefore had to consider government misconduct beyond OAT’s failure to use written protocols.

The Commonwealth later notified approximately 27,000 defendants whose OUI cases were implicated. Later orders presumptively excluded affected results, required notice to affected defendants, and established the conditions for any later use of Alcotest 9510 evidence.

The Hallinan Presumption

The Supreme Judicial Court held that defendants who pleaded guilty, admitted to sufficient facts, or were convicted after trial, and whose cases included a result from an Alcotest 9510 device last calibrated and certified before April 18, 2019, receive a conclusive presumption of egregious government misconduct. The device’s calibration and certification history, rather than the date on which the defendant submitted to the breath test, determines whether the result falls within the affected class. An affected defendant need not prove OAT’s misconduct separately, and the judge must exclude the affected result at any later trial.

Counsel should review the instrument model, calibration and certification history, disposition, and the prosecution’s use of the result. A defendant is not entitled to postconviction relief solely because the Alcotest 9510 device was last calibrated and certified before April 18, 2019.

The Required Case-Specific Showing

The Supreme Judicial Court did not establish a conclusive presumption of prejudice. A defendant who pleaded guilty or admitted to sufficient facts must demonstrate a reasonable probability that the defendant would have rejected the disposition and proceeded to trial if the OAT misconduct had been known. The judge examines the totality of the circumstances rather than treating the presence of a breathalyzer result as sufficient by itself.

The judge considers whether the misconduct undermined the factual basis for the disposition, whether the information could have impeached an outcome-determinative witness, whether the information was cumulative, whether it would have influenced defense counsel’s recommendation to accept the disposition, and whether the benefits of the agreement outweighed the value of challenging the breathalyzer evidence.

A defendant convicted after trial must file a Rule 30 motion and establish a legally sufficient basis for setting aside the verdict. Hallinan supplies the conclusive presumption of government misconduct and requires exclusion of the affected result at a later trial, but it does not make the plea-specific factors the standard for a trial conviction. Relief requires an individual Rule 30 motion; the presumption does not reopen or vacate a case automatically.

What an Allowed Motion Changes

If a judge allows a motion to withdraw a plea or for a new trial, the criminal case reopens. The ruling does not by itself dismiss the OUI charge. The Commonwealth may prosecute the charge again without the excluded Alcotest 9510 result, but it may not charge an offense greater than the offense of which the defendant was originally convicted.

If the defendant is convicted again, the new sentence may not exceed the original sentence if the original sentence was legal. The defendant must receive credit for incarceration already served and for the portion of any license suspension already served as a result of the original criminal disposition. If the original sentence was illegal, the new sentence is not capped by that illegal disposition. The sentencing court should also account for completed treatment programs and other previously satisfied sentencing conditions.

When an Older OUI File Should Be Reviewed

Under Massachusetts Rule of Criminal Procedure 30(b), a judge may grant a new trial at any time if it appears that justice may not have been done. The judge applies that standard to the evidence accompanying the motion, and an appellate court reviews the ruling for abuse of discretion or significant legal error. An older case can present practical proof problems. Counsel should obtain the docket, plea or trial record, police reports, breath-test documents, instrument records, and information about the sentence and license consequences before deciding whether to file a motion.

In a later matter, a court or the Registry may consider an earlier Massachusetts OUI disposition when applying the statutes governing prosecution, suspensions for refusing the breathalyzer, ignition interlock, or licensing. Each provision defines the relevant prior offense separately. An earlier OUI disposition does not necessarily lengthen every later suspension.

Hallinan Checklist for Clients and Lawyers

What the Client Should Gather

• The court, docket number, approximate date of the OUI case, and any later court date involving that disposition.
• The disposition, including whether the case ended by a guilty plea, an admission to sufficient facts with a continuance without a finding, or a conviction after trial.
• The police report, breath-test ticket, docket, plea papers, and any notice concerning the Office of Alcohol Testing or Alcotest 9510.
• A record of probation, treatment programs, incarceration, fines, and the license suspension completed because of the criminal disposition.
• Any available information about how the breathalyzer result affected the decision to accept the disposition or the evidence presented at trial.

What Counsel Must Verify

• Whether the test was performed on a Draeger Alcotest 9510 and whether that device was last calibrated and certified before April 18, 2019.
• Whether the breathalyzer result formed part of the plea’s factual basis, influenced the disposition, or was admitted at trial.
• For a plea or admission, whether the record establishes a reasonable probability that the defendant would have rejected the disposition and proceeded to trial.
• For a trial conviction, whether the record establishes a legally sufficient basis for relief under Rule 30 without importing the plea-specific factors.
• The strength of the remaining evidence, the legality of the original sentence, the credit due for incarceration and the disposition-based license suspension, and the completed treatment programs or other conditions the sentencing court should take into account.

Current Breath-Test Challenges

Hallinan concerns identified government misconduct and affected older Alcotest 9510 devices. It does not create a presumption that current breathalyzer results are unreliable. Current cases require review under the statutes, regulations, records, and scientific issues that apply to the particular breath test.

The Massachusetts breathalyzer-defense page explains the current evidentiary foundation, records, and grounds for a motion to exclude. The breath-test and blood-alcohol-science guide addresses the instrument, physiology, mouth alcohol, and test timing. The Massachusetts breath-test and BAC FAQs provide concise answers about breath and blood evidence.

Attorney Joe Serpa has practiced Massachusetts criminal defense since 1995. Serpa Law Office reviews older OUI dispositions involving affected Alcotest 9510 evidence and current cases in which the Commonwealth seeks to use a breathalyzer result. Call 617.936.0201 for a free and confidential consultation.

Last reviewed August 30, 2026.