The filing marked the first salvo in a battle the lawyers have long said will be won or lost in the higher courts.
The archdiocese is paying Bergstrom and Khaskelis, of the Buchanan, Ingersoll & Rooney law firm, to lead the appeal. Tauber and his partner, Jeffrey Lindy, were part of the monsignor's defense team during his landmark trial earlier this year.
Their 23-page argument mirrors claims they made to Lynn's trial judge, Common Pleas Court Judge M. Teresa Sarmina. Twice she rejected requests to free Lynn on bail, declaring that his crimes were too serious and his sentence too long.
Lynn is serving 3 to 6 years in state prison after a Common Pleas Court jury found him guilty of endangering children when he was secretary for clergy under Cardinal Anthony J. Bevilacqua.
Lynn, who managed archdiocesan priests assignments, let one remain in active ministry at a Northeast Philadelphia parish in the 1990s despite concluding that he had once abused a minor. That priest, Edward Avery, later sexually assaulted a 10-year-old altar boy.
Lynn has been jailed since his June 22 conviction, most recently at Camp Hill state prison, ostensibly awaiting a permanent assignment.
The defense lawyers say that the Philadelphia District Attorney's Office used a "novel and controversial" theory to charge Lynn with endangering children in the 1990s even though the child-endangerment statute at the time didn't specifically cite supervisors like him.
They maintain that District Attorney Seth Williams' office applied that 1990s law even after his predecessor, Lynne Abraham, had concluded that the same law didn't cover child-care employers or supervisors. No one was charged after Abraham's two year grand-jury investigation.
That's one reason, they said, that Philadelphia prosecutors "zealously advocated" for a 2007 amendment to state law to make child-care supervisors criminally liable for their employees conduct.
"It is clear beyond a reasonable doubt that there are substantial grounds for a difference of opinion as to whether Msgr. Lynn could have been lawfully prosecuted under the statute utilized by the Commonwealth," the lawyers wrote in their motion.
They also took aim at the judge, asserting that Sarmina bungled instructions to the jury and failed to properly define "supervisor" for them.
The defense also signaled its intention to appeal Sarmina's decision to let prosecutors introduce decades worth of evidence of sex abuse by archdiocesan priests, including allegations lodged decades before Lynn became the secretary of clergy or, in some instances, before he even became a priest.
Roughly half the three-month trial was spent presenting that evidence and testimony from nearly 20 alleged victims of those priests.
Prosecutors have countered that such evidence was admissible because it showed that Lynn and other archdiocesan leaders knew the signs of sexually abusive priests, and that his decisions reflected a long-standing and accepted practices by the church to hide and protect pedophile priests.
Tasha Jamerson, a spokeswoman for the prosecutors' office, said it would have no comment on the bail motion.
Contact John P. Martin at 215-854-4774, at firstname.lastname@example.org or follow @JPMartinInky on Twitter.
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