"I just think she needs to be careful," Corbett said last week in an interview with Inquirer editors and reporters. He said Kane had a right to review his office's actions and has promised to cooperate, but added, "I don't know how you would risk an investigation."
Kane's pointed portrayal of Corbett as slow-footed in pursuing Sandusky was a major message in the campaign that made her the first Democrat and first woman elected to Pennsylvania's highest law-enforcement post.
It fit into Kane's broader theme that Harrisburg is run by a "good-old-boy" network that takes care of itself.
"In many ways her victory was built upon Tom Corbett, so their political fortunes are now linked," said Christopher Borick, pollster and political scientist at Muhlenberg College in Allentown. "If people see her spending most of her time hounding Corbett, that will get old fast. You have to do due diligence, but you can't go over the top with it."
Kane, sworn into office Jan. 15, has not spelled out precisely how she's going to handle the investigation, except to say that she will designate an in-house prosecutor to direct it. That person - who has not been named - will be given the unenviable task of second-guessing the work of colleagues in the Attorney General's Office.
"It's got to be bad for office morale," said George Parry, a veteran Philadelphia defense lawyer and former prosecutor. "You knock yourself silly putting together this case, the bad guy is in jail, and then you wind up being investigated by your own office."
Through a spokeswoman, Kane declined to comment for this article.
Kane, a former Lackawanna County assistant district attorney, has contended that Sandusky should have been arrested as soon as the first young accuser came forward - the better to get a dangerous predator off the street, rather than taking the slower route of convening a grand jury, as Corbett did.
Corbett, a career prosecutor before he ran for governor, has bristled at this critique. He said in the Inquirer interview that use of a grand jury was crucial to building a strong enough case to stand up against Sandusky, a popular coach in the revered PSU football program who also was held in high regard for his charity that helped troubled boys.
"The criticism that Ms. Kane has is that she would never have put this in a grand jury," Corbett said. "My observation is, I don't think she's ever been involved in a grand jury or understands how it operates."
(Kane's campaign biography credits her with having led two grand jury investigations, of a local judge and a charity.)
Corbett continued, "I have done a lot of grand jury work, and my attorneys did a lot. . .. You get a lot of work done and get people to be a little more truthful in a grand jury, because they're not afraid of something getting out. In a little neighborhood like [State College], it's hard to keep secrets."
The explosive Sandusky case first came to the Attorney General's Office early in 2009 when a teenage boy told authorities he had been molested repeatedly by the former coach. It was referred to Corbett's office because the Centre County prosecutor had a conflict of interest.
The grand jury investigation inched along for months, Corbett said, until an anonymous tip led investigators to former assistant coach Mike McQueary. His account of having seen Sandusky sexually assault a boy in a locker-room shower "led to everything else," as Corbett put it. But by then, Corbett had been elected governor and the case was proceeding under his handpicked successor, Linda Kelly.
Thirty-three months elapsed between the first complaint and Sandusky's being charged in November 2011.
Democratic critics have contended that by kicking the matter to a grand jury, which typically takes longer to bring charges, Corbett avoided having a controversial case play out when he knew he would be running for governor.
Corbett, in the Inquirer interview, said that was ridiculous. He not only defended the use of a grand jury as a proven investigative tactic in sex-crime cases; he said that politically, he would have benefited if Sandusky had been convicted during the gubernatorial campaign - and that, Corbett said, would have led critics to rip him for exploiting the case.
"I can't win either way," he said.
As Corbett noted, an attorney general investigating decisions of a predecessor is not unprecedented. In fact, Corbett himself once did it.
After he was appointed attorney general in 1996, he launched a review of $441,000 in legal fees billed to the taxpayers while his predecessor, Ernie Preate, was under federal investigation for taking unreported cash campaign contributions from operators of illegal video poker machines during Preate's earlier career as Lackawanna County district attorney.
Corbett had been appointed to the post by Gov. Tom Ridge after Preate was convicted and resigned. Contending it was improper to charge taxpayers for Preate's personal defense, Corbett hired a special counsel to investigate the matter. The law firm defending Preate argued that its work was done to protect the Office of the Attorney General and the professionals working there, and that Preate paid for work done on his own behalf. Corbett eventually handed the case over to federal prosecutors, and the law firm reached a settlement.
"There's nothing unusual about an attorney general wanting to know if her people are carrying out their responsibilities properly," Harrisburg lawyer Walter Cohen, a Republican who once served as acting state attorney general, said in an interview. When he was first deputy under Preate, Cohen recalled, he reviewed the handling of a previous consumer-protection case to see whether it was in line with the new attorney general's priorities.
Kane is preparing "a legitimate inquiry," Cohen said. "It's appropriate for her to know if there were people within the office who were part of a delay in a child-abuse case."
Less clear is where the investigation might lead. Legal experts say that the key question - whether to use the slower grand jury process in such a case - is a matter of a prosecutor's discretion.
"That's just a difference of opinion on how to proceed," Parry said. "I wouldn't launch an investigation of a crucial prosecution by my predecessor on that alone." He added, however, that it's possible Kane has information or leads she has not disclosed.
Some warn that Kane risks jeopardizing the remaining parts of the Sandusky case that are now her office's responsibility - she could even be called as a witness for the defense in trials of three former Penn State officials now facing charges. Or, at the very least, the fact of her probe into possible political considerations could be used by defense counsel to create doubt in jurors' minds.
In theory, Kane's review could also turn up evidence that would undermine the pending prosecutions of former PSU president Graham B. Spanier and administrators Gary Schultz and Tim Curley, Parry said.
"A lot of stuff sounds great on the campaign trail until you sit down and look at it," Parry said.
But Bruce Antkowiak, a law professor at St. Vincent College in Latrobe, said that the mere suspicion of political decision-making was not enough.
"I don't see that as being a viable line of defense," said Antkowiak, who has served as a special counsel for the state Attorney General's Office several times, including under Corbett. "You would have to have some evidence of personal animus toward the person, evidence the prosecution was brought against them in bad faith."
In the cases against Spanier, Curley, and Schultz, prosecutors already are obliged to turn over any exculpatory evidence to the defense, and Kane's checking of the voluminous Sandusky file would provide a kind of "double security" for this requirement, the law professor said.
Unless Kane finds evidence that Corbett or his underlings actually ordered the case slow-walked, Antkowiak said, it is unlikely the investigation will wind up harming the governor. "It's tough to just go back and question that decision about the grand jury," he said. "That is not a decision that is made lightly."
The governor said he was confident he that he did nothing wrong and that he does not believe Kane's probe will interfere with his current job. He also pointed again to Sandusky's eventual conviction on a slew of criminal charges as a vindication of the use of the grand jury.
Corbett took a moment during the interview to put himself in the shoes of Kane's investigators, questioning other investigators who worked for him on early phases of the Sandusky case.
"The only question . . . is, 'Did Gov. Corbett tell you to slow down this investigation until after the election?' " he said. "I know the answer to that. I never said that. Never. Absolutely never."
Contact Thomas Fitzgerald at email@example.com or 215-854-2718, or follow @tomfitzgerald on Twitter. Read his blog, "The Big Tent," at www.philly.com/bigtent.