ROCKLAND, Maine — An investigation into potential wrongdoing by a former drug enforcement agent could jeopardize 44 criminal cases pending in Knox County.

The former agent is the subject of a MaineCare fraud investigation by the Maine Attorney General’s Healthcare Crimes Unit, according to multiple sources.

The name of the agent and the circumstances behind the investigation are currently sealed under a court order, but a month-long examination by the BDN of available court documents has determined the officer is Kirk Guerrette, a former Maine Drug Enforcement Agency investigator and current patrol administrator for the Knox County Sheriff’s Office.

Attorney Jeremy Pratt of Camden, who represents 14 of the defendants in the 44 cases, learned in December that Guerrette was “under investigation for wrongdoing” and filed motions to crack the court seals and reveal investigators’ reports about Guerrette. The defendants hope to obtain materials to undermine Guerrette’s credibility as a witness in their cases.

Several messages left for Guerrette seeking comment were not returned.

Justice Jeffrey Hjelm will hear from the parties involved to decide what information, if any, will be released and to whom on Monday, March 7, in Knox County Superior Court.

Among the materials defense lawyers are seeking to make public is a four-page report about the ongoing Healthcare Crime Unit’s investigation which was written by Attorney General Detective Jeffrey Wrigley.

The BDN has determined that Guerrette is the subject of the report, but the information it contains is so secret that even he and his attorney haven’t seen it.

The subject of the report is not identified in court documents by name and is referred to by the random initials “A.B.” Attorney Melissa Reynolds O’Dea of Augusta, who represents A.B., asked the court for the Wrigley report, but was denied.

A.B. “has reason to believe that there are speculative and unfounded allegations against him in the report. Because he has not seen the report, [he] is completely unable to rebut the allegations,” O’Dea wrote.

Michael Miller is the director of the Healthcare Crimes Unit, which is investigating Guerrette. She would not comment specifically on the case, but said her agency is charged with investigating MaineCare fraud and crimes committed by health care providers. The unit would investigate a law enforcement officer only if he were involved in a larger “criminal scheme or conspiracy” that involved a MaineCare provider, Miller said.

In addition to the Healthcare Crimes Unit investigation, Guerrette’s employer, the Knox County Sheriff’s Office, also is conducting an internal review of him, according to MDEA Director Roy E. McKinney. In December, Sheriff Donna Dennison pulled Guerrette from his assignment with the MDEA before his contract with the agency expired. This is when the internal review of the then-detective began. Dennison would not confirm Thursday that Guerrette is under a review, but did say he was promoted earlier this week from detective to lieutenant and named patrol administrator.

McKinney said Thursday, “If a person is sent back to their agency, it can’t be implied that they’ve done something wrong or that they are bad.”

McKinney would not talk specifically about Guerrette, but did say officer credibility is paramount in his department.

“If an officer’s credibility is questioned by the court and has to be reviewed by the court it becomes problematic from a prosecutor standpoint,” McKinney said. “What value is that officer before the court if their integrity is called into question?”

It’s unclear how the documents being sought by defense attorneys will affect Guerrette’s credibility as a witness in the 44 pending drug cases. Depending on the importance of his testimony, some or all of the cases could be dismissed, according to law professor Cab Howard, who works at the University of Maine School of Law.

On Feb. 14, Justice Hjelm ordered the Healthcare Crimes Unit to file all investigation documents and any other materials relating to A.B. that could be relevant to the pending cases. These documents will then be impounded and sealed, Hjelm wrote. At Monday’s hearing the judge will consider arguments about who should have access to the information.

In court documents, the Healthcare Crimes Unit asks the judge to keep the documents hidden, while defendants demand to see them.

“In direct competition with defendant’s rights is the compelling interest of HCU in maintaining the confidentiality of its intelligence and investigative information,” Miller wrote in court documents. “Disclosure of the HCU information would prematurely reveal the scope, nature and direction of HCU’s case, allow suspects to construct defenses, and create a possibility of evidence destruction, witness harassment or intimidation.”

The investigation is complex and involves many people, Miller wrote. Even if the people who saw it were sworn to secrecy, it could still get leaked and foil the unit’s work.

O’Dea argues that she and her client should see the documents, but that no one else should. The information, she said, contains his confidential medical information. Further, she wrote, it “allows the public to draw adverse inferences about [name withheld]. Those inferences are extremely damaging to [his] reputation and credibility.”

However, she wrote to the court, she should see the documents so she may rebut the “speculative and unfounded allegations against him.”

The 44 cases, which date from September 2008 to January 2011, might be the beginning of a much longer list, according to one defense attorney, speaking anonymously because of the court order.

“There could have been a bunch of people who have been convicted who aren’t part of the 44 who have been convicted based on the testimony of Kirk Guerrette,” the attorney said. “The prosecution’s office shouldn’t just be looking at the open cases but also the closed cases. And there could be hundreds of closed cases where people are in prison and maybe shouldn’t be.”

In the BDN’s examination of the 44 pending cases, Guerrette is listed as lead investigator in 34. Court documents and sources tie him directly to three others. The seven remaining cases lack police reports. Guerrette is the only person listed in 11 of the court files. His MDEA supervisor is the second most listed name, appearing in 12 of the cases.

Guerrette has been with the Knox County Sheriff’s Office for more than 20 years, according to his boss, Sheriff Donna Dennison. In June 2007 he began his assignment with the MDEA. He was scheduled to continue his work there until June 2011. When he was pulled from his assignment, Dennison promoted him from detective to the lieutenant position of patrol administrator, a job he had wanted for a while, she said.

Dennison sounded supportive of her lieutenant when asked to comment this week. But she said her hands were tied and that she could not say much to the press about personnel issues. She hopes that she and Guerrette will soon be able to talk to the public.