HARRISBURG — Lawyers for two Penn State University administrators remained bullish Thursday on their clients’ chances of acquittal despite new evidence suggesting the men knew of sex abuse allegations against Jerry Sandusky but decided not to report them.

Still, the defense lawyers said, the ever-expanding parameters of the prosecutors’ case — now including a sheaf of seemingly incriminating e-mails released over the past few months — has made it near impossible to prepare an effective defense.

“We are on shifting sands,” said Caroline Roberto, a lawyer representing suspended university athletic director Tim Curley. “We need an end point. We need a determination. We need to know what we are defending against so we can move forward to trial.”

Roberto’s comments came during a pretrial hearing in Dauphin County court for Curley and former Penn State vice president Gary Schultz, who face charges of perjury and failing to report abuse in connection with the Jerry Sandusky child sex abuse scandal.

Prosecutors allege the pair failed to notify outside authorities when graduate assistant Mike McQueary told them in 2001 that he saw Sandusky molesting a boy in a football locker room shower. Both also stand accused of later lying about it to a grand jury investigating the former assistant football coach a decade later.

Curley and Schultz have maintained that McQueary never made clear to them the sexual extent of what he saw and have said as they understood it, the graduate assistant was describing mere, if questionable, “horseplay.”

But while the case began last year as a war of words — McQueary’s version of events against theirs — prosecutors’ ongoing investigation has since uncovered e-mails from 2001 suggesting Curley and Schultz, along with former university president Graham Spanier, understood McQueary’s allegations were at least serious enough to consider alerting outside authorities.

The trio debated whether to report Sandusky, before ultimately deciding to handle the matter internally in an e-mail exchange that stretched over several days.

At Wednesday’s court hearing, defense lawyers challenged the addition of those e-mails as trial evidence and sought to have the perjury counts tossed, arguing prosecutors were wielding the charge to punish the administrators for the decisions they made rather than any specific lies they may have told.

“The fear is that this will become a trial about whether Mr. Curley or Mr. Schultz exercised the proper judgment. That isn’t what a perjury case is about,” said Schultz’s attorney Thomas J. Farrell. “The jury will say: ‘We don’t like the way they responded, so we’ll convict them.’”

In fact, the lawyers said, Curley and Schultz’s grand jury testimony syncs nearly perfectly with McQueary’s, even though the conclusions they reached were worlds apart.

Testifying at a preliminary hearing in December, McQueary said he made clear to both administrators that while he was not close enough to make out an explicit sex act between Sandusky and the child, he saw them naked together and engaged in an encounter he described as “way over the line.”