Philadelphia (CNN) -- Jurors started to deliberate Friday in Philadelphia in the landmark trial of Monsignor William Lynn, the highest-ranking cleric charged with endangering children by allegedly helping cover up sexual abuse.
Lynn, a defendant with another Philadelphia priest, is accused of knowingly allowing dangerous priests to continue in the ministry in roles in which they had access to children.
Also on trial is the Rev. James Brennan, who is accused of the attempted rape of a 14-year-old. Both Brennan and Lynn have pleaded not guilty.
Closing arguments in the case concluded Thursday.
Lynn's defense team argues that the monsignor repeatedly sent word of child sex abuse up the chain of command.
He operated under strict orders from the late Archbishop Cardinal Anthony Bevilacqua, and never had the power to remove a priest from ministry, the defense team argues.
It said Lynn was never formally trained to handle child sex abuse allegations and learned on the job.
"The allegation is that he did nothing, but he didn't do nothing," said Thomas Bergstrom, Lynn's defense attorney
"They want you to convict him for their sins. He held more than a candle to their shame, he put a spotlight on their shame," Bergstrom told jurors.
Lynn donned his clerical garb, surrounded by numerous family members, priest friends and parishioners inside the courtroom.
Lynn is the first high-ranking church figure charged with child endangerment for allegedly shuffling predator priests from parish to parish.
If convicted, he faces up to 21 years in prison.
Now-defrocked priest Edward Avery was due to go on trial with Brennan and Lynn, but he pleaded guilty in March after admitting to sexually assaulting a 10-year-old altar boy during the 1998-1999 school year.
Avery, 69, was sentenced to two-and-a-half to five years in prison.
More than 60 witnesses and alleged victims of clergy abuse have testified since the criminal trial began March 26.
Accusers for Brennan and Avery have claims that fall within the statute of limitations.
Brennan's accuser, now in his 30s, was a former altar boy who cried on the stand weeks earlier as he described the incident. The man, a former Marine, was discharged because of mental health issues.
"He will say anything at all to get what he wants," Brennan's attorney, William Brennan, no relation to the defendant, told jurors about the accuser. "Plug that into your credibility meter."
Brennan was removed from active ministry in 2006 after his accuser first came forward. He admitted in 2008 that he allowed the then-14-year-old to view pornography and sleep in the same bed with him during an overnight visit in 1996, according to testimony given to church investigators.
Brennan did not testify at the trial.
His attorney urged jurors to use their "common sense" once they begin deliberations.
"It's a mistake, it's poor judgment," Brennan told jurors of the sleepover. "I can't believe a jury would destroy this man's life over that."
A 2011 grand jury report led the Philadelphia district attorney's office to criminally charge four Philadelphia priests and a parochial school teacher with raping and assaulting boys in their care, while Lynn was accused of allowing the abusive priests to have access to children.
The trial marks the first time U.S. prosecutors have charged not just the priests who allegedly committed the abuses, but an official -- Lynn -- who stands accused of failing to stop the assaults.
A gag order bars all parties involved in the criminal case from talking to the media.