The retrial of Msgr. William J. Lynn for his supervisory role in the Philadelphia Catholic Church clergy sex-abuse scandal will go forward.

When, is another question.

On Friday, a Philadelphia judge rejected a defense motion to dismiss the child-endangerment charge against Lynn because of prosecutorial misconduct.

But in ruling, Common Pleas Court Judge Gwendolyn N. Bright gave Lynn's lawyers the right to appeal her decision to the state Superior Court, a move that could delay a retrial – originally set for May -- for months or years.

Lynn, 66, the first Roman Catholic Church official convicted for his supervisory role over priests accused of sexually abusing children, served 33 months of a three-to-six-year prison term before he was released in August after a state appeals court granted a new trial.

Since then, Lynn's lawyers and the District Attorney's Office have been arguing a series of legal issues in preparation for the retrial.

The key issue, which Bright decided Friday, was the defense motion to dismiss the charge for prosecutorial misconduct: the failure to tell Lynn's lawyers about a detective's doubt about the credibility of one of the key prosecution witnesses at Lynn's 2012 trial.

Bright said the information should have been turned over but added that she did not consider it "intentional prosecutorial misconduct." And she said the impact on Lynn's defense did not warrant the extreme penalty of dismissing the charge against the cleric.

Defense attorney Thomas A. Bergstrom has 30 days to decide whether to appeal Bright's ruling to Superior Court and he said he is considering doing so.

Court rules require prosecutors to give the defense any "exculpatory evidence" – evidence suggesting a person's innocence – before trial. Bergstrom argued that prosecutors violated that rule by not revealing before Lynn's 2012 trial that a police detective had told one prosecutor he had strong doubts about a key witness' credibility.

At a hearing in January, retired Philadelphia Police Detective Joseph Walsh testified about a  pretrial witness-preparation session in January 2012, a month before the start of Lynn's trial.

Walsh had been called back to work by the District Attorney's Office to prep a 23-year-old man who claimed he had been molested by two priests and a parochial-school teacher.

Walsh testified that he could not get the 23-year-old to explain numerous inconsistencies in his story of being molested in 1998 and 1999 while he was a 10-year-old altar server at St. Jerome's parish in the Northeast.

Walsh said the accuser said he was sexually molested by two priests at St. Jerome's parish. One of the alleged assaults lasted five hours after he served the 6:15 a.m. Mass.

But Walsh said there was no record of the accuser serving those Masses, including on his mother's home calendar where she recorded her sons' various church assignments.

The accuser also said he was a member of the parish bell choir and the "bell crew" although three teachers involved with that program could not corroborate that.

Walsh testified that several times in late 2011 he told Assistant District Attorney Mariana Sorensen, a prosecutor on the investigation, about his doubts.

Walsh testified that Sorensen said she believed the witness and complained, "You're killing my case."

Walsh, however, said he could not recall if he warned Sorensen after the preparation session and before the start of trial.

Prosecutors said Sorensen has denied making those statements to Walsh.

The Inquirer's policy is not to identify sexual abuse victims or accusers.

The accuser did testify at Lynn's 2012 trial in which the archdiocesan official was convicted of child endangerment for his supervisory role over deviant priests.

The credibility of the accuser — identified as "Billy Doe" in court filings — was central to the convictions of Lynn, two priests, and a parochial-school teacher.

Lynn was accused of letting the Rev. Edward V. Avery, who had a history of sexually abusing children, live in the St. Jerome's rectory. There, in 1999, Avery was accused of assaulting the boy.

The accuser also testified that he was sexually assaulted by another St. Jerome's priest, the late Rev. Charles Engelhardt, and teacher Bernard Shero.

Despite aggressive defense questioning of the accuser about his criminal history, drug use, and multiple versions of his assaults, Philadelphia juries convicted Lynn, Engelhardt, and Shero. Avery pleaded guilty to sex-assault and conspiracy charges. All four men were sentenced to prison.

Bergstrom said a decision about appealing Bright's ruling will not be made until after a hearing Tuesday on two other evidentiary issues in the case.

One issue involves the number of other cases of sexual assault on children by priests that may be told to the jury. Lynn was the Archdiocese of Philadelphia's secretary for clergy from 1992 to 2004, responsible for investigating allegations against priests and recommending action to the archbishop.

Prosecutors argue that evidence of how Lynn handled other accused priests is needed so that the jury will understand how Lynn was part of a deep-seated church culture of ignoring victims and covering up for deviant priests.

A second issue involves whether defense lawyers may question Avery without prosecutors being able to raise his guilty plea. Avery has since denied that he molested "Billy Doe" and said he only pleaded guilty to escape a longer prison term if convicted at trial.