The panel got the case after Spanier's attorneys declined to call any witnesses to counter accusations he acted illegally in handling a 2001 complaint about Sandusky, a former assistant football coach, showering with a boy. Deliberations were scheduled to resume Friday.
In a closing argument, Spanier attorney Sam Silver said there was "no evidence" and the case involved judgment calls by high-ranking university administrators in dealing with the complaint Sandusky had been seen naked with the boy in a team locker room.
"They made judgment calls," Silver said. "They did not engage in crimes. They did not enter in a conspiracy."
Prosecutor Laura Ditka said Spanier, former athletic director Tim Curley and former vice president Gary Schultz took actions to preserve the university and their own reputations, at the expense of children.
"They took a gamble," Ditka told jurors. "They weren't playing with dice. They were playing with kids."
Spanier, who didn't testify, faces three felonies. Curley and Schultz struck plea deals last week to a misdemeanor count of child endangerment and testified against Spanier.
Spanier was forced out as president in 2011, after Sandusky was charged with child molestation and Curley and Schultz were charged over their handling of the matter. Spanier was charged a year later.
Sandusky has been in prison since his 2012 conviction on dozens of counts of child sexual abuse and was expected to be in a courthouse near campus Friday for an appeal hearing. He insists he's innocent.
During deliberations, the Spanier jury twice returned to the courtroom, asking the judge about what makes someone a supervisor of a child under the law, what constitutes a criminal conspiracy and how the law defines reckless.
The abuse scandal sent shockwaves through the Penn State community, led to the firing of Hall of Fame coach Joe Paterno, who died of cancer in early 2012, and ultimately led the university to pay more than $90 million to settle civil claims.
Silver called Spanier, Curley and Schultz "good men" who took seriously the 2001 complaint by then-graduate assistant coach Mike McQueary.
He urged jurors to focus on testimony by Schultz and Curley that they never told Spanier that McQueary had reported seeing something sexual, although McQueary's testimony was that he did tell the two of them it was sexual in nature.
"Mr. Schultz made clear - he, Gary Schultz, told Graham Spanier that it was horseplay," Silver said.
A key piece of evidence was an email exchange in which the three debated what to do.
Spanier OK'd having Curley tell Sandusky to stop taking children to athletic facilities and inform The Second Mile, a charity for at-risk youth founded by Sandusky. An earlier plan had involved informing the state Department of Public Welfare, but Spanier approved putting that on hold, and the agency was never contacted. That failure to make a report forms the heart of the criminal accusations against him.
"The only downside for us is if the message isn't 'heard' and acted upon, and we then become vulnerable for not having reported it," Spanier told Curley and Schultz in the 2001 email exchange.
Silver said several people knew of McQueary's complaint and The Second Mile's director was informed.
Ditka began her closing argument with reference to the "only downside for us" quote and repeated it several times, urging jurors to convict.
"All they cared about was their own self-interest," Ditka said, arguing the three men "let (Sandusky) run wild" despite knowing he had been the subject of complaints in 1998 and 2001.
The 1998 complaint, from a woman upset that Sandusky had bear-hugged her son in a team shower, was investigated, but the district attorney declined to file charges.
Ditka said McQueary told Curley and Schultz he saw Sandusky behind a prepubescent boy, in a dark shower at night, with his hips moving slightly.
"Do you think that's horseplay?" she asked jurors.
She dismissed any idea three of the university's top leaders would have immediately launched a series of meetings and discussions if they really thought it was just horseplay.
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