A District Court judge has decided that no Breathalyzer tests administered in Massachusetts can be used in court until the state’s Office of Alcohol Testing undergoes major reforms.

The ruling by Judge Robert Brennan comes after years of litigation over the reliability of the Breathalyzer test that is used in Massachusetts. During the course of the litigation, it was discovered that the Office of Alcohol Testing intentionally withheld important evidence from defense lawyers.

Despite a state investigation of the office and the promise of reforms, Brennan wrote that none of the steps taken so far are “sufficient to provide the level of transparency necessary to remedy the harm to the criminal justice system.”

Joseph Bernard, of Springfield, and Thomas Workman, of Taunton, representing drunken driving defendants, have been challenging the accuracy of the Alcotest 9150 developed by Draeger Safety Diagnostics.

Brennan ruled in February 2017 that a lack of reliable standards by the Office of Alcohol Testing imperiled the use in court of Breathalyzer tests calibrated between June 2012 and September 2014. Brennan found that the test is reliable, but the way the state maintained the tests was not.

The case took on a new twist in August 2017 when the judge found that OAT had not disclosed important evidence. After a judge ordered the office to provide all calibration and certification worksheets for the test, state officials provided 1,976 worksheets – but intentionally withheld 432 worksheets that showed failed calibrations.

The technical leader of the office was fired.

By 2018, the state’s district attorneys had agreed to toss out evidence from tens of thousands of drunken driving cases.

The Executive Office of Public Safety and Security conducted an internal investigation of OAT in 2017, and that investigation, as described in Brennan’s latest decision, “identified various instances of intentional withholding of exculpatory evidence, blatant disregard of court orders, and other errors, all underscored by ‘a longstanding and insular institutional culture that was reflexively guarded at OAT.’”

Public Safety Secretary Daniel Bennett ordered OAT, which is part of the state police crime lab, to make changes to its operations, particularly related to discovery.

The office plans to apply for accreditation from a national accreditation board by August 2019. It is providing additional training for employees and putting in place new standards about complying with discovery requests.

The state argued that it should be allowed to use Breathalyzer tests done after Aug. 31, 2017, which is when OAT released all the failed worksheets. Bernard and Workman said the Breathalyzer should not be considered reliable until OAT receives accreditation.

Brennan’s ruling says OAT cannot use the tests in court until it proves that its methodology will produce scientifically accurate results. Brennan wrote that this can be accomplished by OAT filing an application for accreditation that is likely to be approved.

OAT must also write discovery protocols consistent with those used by the state police’s crime management unit, and must train its staff in how to comply with discovery requests.

The accreditation application and discovery protocols must be made public.

Clarification: According to the Suffolk District Attorney’s office, based on a voluntary agreement by prosecutors, breath tests can be introduced as evidence in cases of OUI motor vehicle homicide, OUI causing serious bodily injury, and OUI as a 5th or subsequent offense, if it is proven that the device was calibrated correctly. They will not be used in other cases.