HARRISBURG — Gov. Tom Corbett knew Penn State was going to be facing the worst crisis in its history, but his inability to warn other school trustees about the Jerry Sandusky child sex abuse case before the former assistant coach’s arrest has critics questioning which role should have been more important: school leader or a former prosecutor.

Corbett’s unique dual role — Penn State trustee and the state’s former attorney general — came into focus once again with last week’s release of an investigative report by former FBI Director Louis Freeh. It criticized an out-of-touch board for its lax oversight of the university, and for failing to probe deeply enough when it learned of the grand jury probe six months before Sandusky’s arrest.

“His fiduciary responsibility as a board member to put the university first was almost certainly compromised by both his own personal involvement and his role as governor who must put the interests of the state first,” said Barbara Doran, a Penn State graduate who narrowly lost election to the board this year.

Corbett couldn’t tell his colleagues even if he wanted to. As the former state attorney general whose office had spent the past two years building a case against Sandusky, he was bound by a legal straitjacket — the state law that cloaks grand juries in secrecy.

“I was not in the position to tell them anything while this was going on,” he said Thursday following an unrelated news conference.

More than anyone else, Corbett was in a position to prepare the board for a scandal that has seriously tarnished Penn State’s reputation. But Jules Epstein, a professor at Widener University School of Law in Delaware, said Pennsylvania law “absolutely prohibited Mr. Corbett from disclosing this information to the Board of Trustees.”

As attorney general, “Mr. Corbett’s job was to investigate crimes, get them investigated well, and not to blow an investigation by telling anyone else prematurely,” Epstein said.

A trustee would normally have an obligation to share potentially damaging information with fellow board members or the school’s administration, said Richard D. Legon, president of the Association of Governing Boards of Universities and Colleges.

As a full voting member of the board, Corbett has all the same rights and responsibilities as any other trustee, including a responsibility to “support the university’s mission” and “act ... at all times in the best interests of the university,” according to the board’s governing documents.

Corbett’s spokesman Kevin Harley contended it was “neither his duty nor his obligation” to alert the trustees about the Sandusky investigation. Historically, governors do not enmesh themselves in board issues.