By Matt Rivers

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PHILADELPHIA (CBS) — The prosecution of a Catholic priest accused of molesting a former altar boy is on shaky ground, after the accuser was found dead, the victim of an apparent drug overdose (see related story).

Father Robert Brennan was arrested last month after a month long investigation by the Philadelphia District Attorney (see related story). A former altar boy who was supervised by Brennan at Resurrection of Our Lord Church said he was abused for three years from 1998 until 2001.

Brennan had also been accused of abuse on at least twenty separate occasions, all of them laid out in a grand jury report released in 2005.  He was never charged, however, because at that time, none of the accusations fell within the crime’s statute of limitations.

Last month’s accuser was the first person to allege crimes that fell within the statute’s timeframe.

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“All of us who got to know this victim are heartbroken and in shock,” said Marci Hamilton, the victim’s lawyer.

Legal experts said Friday that in order for this case to move forward, other potential victims would have to come forward.  Former Philadelphia District Attorney Lynne Abraham, who convened the grand jury that first shed light on the Catholic Church’s cover-up culture, said she remains convinced there are other victims out there, and urged them to come forward.

“There is a way forward out of the darkness by coming forward and telling your story because it’s a story that needs to be told,” said Abraham.

That can be easier said than done, said  John Salveson, an abuse victim counselor and advocate for ending child abuse.  But he said those who do come forward often say the experience is empowering, while helping people.

“That would be a huge service to the community and to other victims.  That would be amazing,” said Salveson.

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