ROCKLAND — The state has dropped a drunken-driving case against a Union man in which the chief witness was a former Rockland police officer accused by a judge of dishonesty.

A criminal OUI charge against Earle J. Studley was dismissed Wednesday by the district attorney’s office.

Studley had pleaded guilty in March 2015 to charges of criminal operating under the influence and unlawful possession of Suboxone stemming from an Oct. 11, 2013, traffic stop in Rockland, and received a two-year deferred disposition.

Before his scheduled sentencing in July 2017, however, allegations arose about then-Officer Jacob Shirey, who had pulled him over.

Shirey resigned in January 2017 from the Rockland Police Department. The city said at the time that he resigned for personal reasons.

Justice Daniel Billings issued a ruling June 22 in Knox County Superior Court allowing Studley to withdraw his guilty plea to the drunken-driving charge. Billings said Shirey had exhibited an ongoing pattern of dishonesty that raised questions about any matter where his credibility was material to the outcome.

Billings urged the district attorney’s office to review prior convictions involving Shirey.

District Attorney Jonathan Liberman announced Wednesday that his office would review all current and closed cases in which Shirey was involved.

“The integrity of convictions obtained by our office is of the utmost importance,” Liberman said in a news release on Wednesday.

Liberman said Shirey was involved in more than 300 cases, but prosecutors will focus on those in which the outcome hinged on the former officer’s testimony and statements.

The region’s chief prosecutor said this was the first time since he had become a prosecutor that a situation like this had arisen. He has been in the district attorney’s office since 2011.