A former FBI agent hired by the Archdiocese of Philadelphia to investigate clergy sex abuse concluded that a Bucks County man was telling the truth when he said the Rev. James J. Brennan tried to rape him when he was 14.

Testifying Monday at Brennan's trial, the investigator, Jack Rossiter, said the priest consistently denied any "intentional" sexual contact with the teen when the boy stayed at his apartment in 1996.

But in three interviews with Rossiter a decade later, Brennan gave conflicting statements about why he slept in the same bed with the boy, how long their visit lasted, and his ties to another young man who lived with him when Brennan was stationed at Cardinal O'Hara High School.

In the end, Rossiter said, he sided with Brennan's accuser.

"I believed him," he said, citing a 2006 report he gave church officials.

His testimony opened the seventh week of the landmark child-sex abuse trial, and came on a day when jurors also heard a former Catholic school student describe how his parish priest pinned loincloths to his naked torso and forced him to endure onstage whippings when he played Jesus in a Passion Play production.

For days at a stretch during the trial, Brennan has been a nearly invisible presence, as prosecutors have sought to prove that former secretary for clergy Msgr. William J. Lynn and other church leaders endangered children by routinely failing to act on credible evidence that priests abused children.

But the allegation against Brennan, 48, is a cornerstone of the case, an example of an alleged sexual assault that prosecutors say Lynn might have prevented.

Brennan's lawyer has tried to portray the accuser as a liar who may have been motivated by money or a need to explain away a decade of drug use and petty crime. The lawyer, William J. Brennan, who is unrelated to his client, noted Monday that the archdiocese notified thousands of students and alumni of Cardinal O'Hara about the claim against the priest, but no other accusers came forward.

And he pressed Rossiter to admit that he spent decades chasing bank robbers and terrorists, but had never investigated a child-sex crime until the archdiocese hired his private firm in 2003.

Ultimately, the job meant interviewing scores of accused priests and their accusers, including the former Newtown, Bucks County, altar boy who said Brennan assaulted him.

The alleged victim, whose name is being withheld by The Inquirer, testified that Brennan, a longtime family friend, had showed him online pornography, encouraged him to masturbate, and then forced him to share a bed, where Brennan allegedly pressed his private parts against him. The man said the alleged abuse led him into a decade of drug use, mental health treatment, and petty crime. He has also filed a lawsuit against Brennan, Lynn, and other archdiocese officials, including Rossiter.

Rossiter read for jurors a report that he and a colleague prepared after interviewing Brennan in April 2006. According to that, the priest acknowledged that he let the teen see one Web page because, he said, the boy had threatened to toss his laptop out the window. He also said that he proposed sleeping on the floor, but that the teen objected and told Brennan to sleep in the king-size bed with him.

Brennan denied any sex assault but "when pressed, said unintentional contact could have occurred without his knowledge" according to the report, Rossiter testified under questioning from Assistant District Attorney Jacqueline Coelho. Rossiter's report also noted that a ranking church official said Brennan had claimed the teen "coerced" him into sharing a bed, but that the priest denied saying that.

According to Rossiter's report, Brennan first said that the teen spent two nights at his townhouse and that he, the priest, slept the second night on a couch. But in a later interview Brennan said he couldn't be sure of the sleeping arrangements.

Brennan also told Rossiter that a college freshman who had been living with him at his residence at Cardinal O'Hara High School was a cousin or nephew. But when the ex-agent confronted him later on the point, Brennan conceded they weren't related.

"I don't think he leveled with me," Rossiter testified.

Brennan's lawyer pressed the ex-agent to explain why he didn't explore the possibility that the accuser and his parents might have concocted the allegation to get a payout. He noted that they had filed for bankruptcy months before reporting the abuse claim.

"They were not under investigation," Rossiter said.

Later on Monday, a former Catholic school student from Havertown told jurors how his former parish priest, the Rev. Thomas Smith, subjected him to disrobing and whippings in the name of "authenticity" during a play describing the crucifixion.

The man, now in his 40s, said he and his parents considered it "an honor" when his eighth-grade classmates at Annunciation school in Havertown chose him to be Jesus in the annual play.

During nearly two dozen dress-rehearsals and performances, he said, Smith pulled him aside to a private room, and ordered him to disrobe and stand naked while the priest stood at his waist, pins in his mouth, and carefully affixed a loincloth. During the play, the priest had other students reenact the crucifixion by whipping him with knotted leather straps.

"I had wounds that were ripped open and weren't healing," he said. "My ears were cut open."

He complained to the priest, but Smith insisted it was necessary to maintain the authenticity of the play, the man told jurors. To cope, he said, he began drinking heavily after each performance.

In 2002, the man said, he had a decade of sobriety and reported the claim to the archdiocese. He said he wasn't seeking a payout, just assurances that Smith could not hurt other children.

Instead, he claimed that Lynn told him Smith was a high-ranking church official and a friend, and that the priest was only trying to maintain the authenticity of the reenactment. "I was angry," the man said.

Under cross-examination from defense attorney Jeffrey Lindy, the man noted that Lynn later followed up and offered to provide him counseling services.

Smith was removed from ministry in 2005 and laicized two years later.

Contact John P. Martin at 215-854-4774 or at jmartin@phillynews.com. Follow him @JPMartinInky on Twitter.

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