PORTLAND – Maine’s attorney general has appointed a special prosecutor to direct the state’s investigation into a now-suspended program that harvested brains at the medical examiner’s office.

The appointment of Assistant U.S. Attorney Richard Murphy comes after disclosures that members of Attorney General Stephen Rowe’s department had connections to the program that sent 99 brains to a Maryland lab between 1999 and 2003.

“I want to avoid even the appearance of a conflict of interest with respect to the investigation and subsequent decision-making regarding this matter,” Rowe wrote in a statement released Tuesday.

Murphy, 48, was named special prosecutor last month after state and federal prosecutors announced they were working together.

The U.S. Attorney’s Office in Portland is looking into whether any federal laws were broken. Though Murphy is an employee of that office, he is not involved with the federal investigation, he said.

In the state probe, Rowe has asked the special prosecutor to determine whether any civil or criminal Maine laws were violated.

Murphy, a South Portland native who is in his 15th year as a federal prosecutor in Maine, said his role as special assistant attorney general is temporary, and it will continue until the investigation concludes.

He will not be paid by the state, according to a letter from Rowe.

The letter said Murphy has “total authority and independence to direct these investigative and prosecutorial efforts on behalf of the state of Maine.”

Drew Ketterer, a former Maine attorney general, said Rowe’s decision to appoint an outside prosecutor makes sense.

The key issue is perception, rather than the reality of whether Rowe’s staff could conduct an impartial investigation, Ketterer said.

“It’s just that in the mind of the public, it’s like, ‘Gee, I wish I could investigate myself.’ It just doesn’t sound good,” he said. “This way, it’s somebody completely outside.”