Prosecutors are investigating whether psychiatrists at Massachusetts General Hospital violated state law by failing to report sexual abuse by priests in the 1990s, the Herald has learned.

The probe focuses on whether a panel of MGH psychiatrists called the Priest Treaters Group, which met to discuss at least 17 clergy abusers from 1994 to 1997, ignored the state's mandated reporting statute. That law requires certain parties -- including physicians -- to report all suspicions of child abuse to law enforcement authorities.

"It is my hope their acts will be prosecutable," said Susan Gallagher of Medford, a victims' advocate with the Coalition of Catholics and Survivors who provided information that launched the Suffolk investigation. "But even if they aren't judged criminal, they should be exposed to the public."

Gallagher said she provided Assistant Suffolk District Attorney David N. Deakin, who runs his office's sex crimes unit, with deposition transcripts from a key MGH doctor and other data she said support a case against the psychiatrists. "He was very interested and he is investigating," she said.

A law enforcement source has confirmed the investigation.

Deakin declined to comment yesterday. Office spokesman David Procopio said: "Whenever we receive information that a reporting violation has occurred, we investigate to determine if a crime has been committed. As a rule we do not confirm the identity of people or groups being investigated."

A spokeswoman for MGH, Peggy Slasman, said, "We are not aware of any investigation."

"These individuals were aware of their legal and ethical obligations concerning their patients and the public with regard to safety and confidentiality," she said.

The Priest Treaters Group was composed of a handful of psychiatrists who served as consultants to the archdiocese -- both informally and officially -- on clergy abuse issues. Some treated individual priests accused of pedophilia.

According to depositions in clergy molestation cases, the head of the Treaters Group was Dr. Edwin "Ned" Cassem, a Jesuit priest who chaired the hospital's Department of Psychiatry for 12 years, until 2000. Other MGH psychiatrists in the group, according to Cassem's testimony, included: Dr. Kathy M. Sanders; Dr. Edward Messner; Dr. James Groves; Dr. Cornelia M. Cremens, and others.

Cassem also testified he consulted with two experts on treating adults abused as children: Drs. Bessel van der Kolk and Raphael Ornstein. Much of the work focused on improving the training of priests to prevent sexual misbehavior later in their careers.

Members of the group -- some more than others -- also were presented with the facts of individual offending priests, among them the late John J. Geoghan and Paul J. Tivnan and George Rosenkranz.

Chapter 119, Section 51A of state law does not require doctors and others to denounce admitted child abusers to authorities. Rather, they are required to report if they "have reasonable cause to believe a child under 18 is suffering physical or emotional injury" from abuse.

A six-year statute of limitations lends urgency to the matter for prosecutors.

The law has been widely interpreted to mean that mandated reporters must only report when they know of specific injuries to specific children. However, no one has ever been prosecuted for failing to report -- the penalty is a fine of not more than $1,000 -- and Gallagher and others believe the law should at least be tested.

"The issue has often come up of 'When are we going to prosecute a mandated reporter for failing in their duty,' " said Jetta Bernier a psychologist and executive director of Massachusetts Citizens for Children. "The penalty is so minor. But we have long discussed it as a 'send a message' issue."

Cassem, as head of the Treaters Group, appears to have known the most about the abusers and their victims, according to his testimony. As a Jesuit priest he was not a mandated reporter under the law as it was written before 2002, but as an MGH psychiatrist he was.

"51-A (the mandatory reporting statute) is something that was mandatory education for all of us," Cassem said in a May deposition in the civil case of Gregory Ford vs. Bernard Cardinal Law. But Cassem acknowledged he never contacted authorities about any abusive priest -- despite being intimately familiar with numerous clerics who admitted abuse.

Asked if he ever advised the archdiocese "to contact law enforcement or child protection agencies," Cassem replied: "I don't remember that I did."

Responding to a related question, Cassem suggested he had not been given specific details of alleged abuse. "I don't remember things other than that a person was labeled as someone who had sexually abused children," he said.

When plaintiff's lawyer Roderick MacLeish Jr. asked Cassem if he thought abuse he was hearing about constituted "criminal activity," Cassem replied: "It was long past in the cases where it was reported to me, as far as I know."

Cassem conceded he never asked MGH lawyers if statutes of limitation had expired. He said he did not recall any discussion by the Priest Treaters Group about whether the abuse should be reported.