"We'd suspected it, but we had no evidence," said Harper, 31, a father of three.
Before his statement on Thursday, Matt had denied that Sandusky had abused him. The fourth victim, however, testified that after he, Sandusky and Matt had played racquetball, Matt went into the shower and he and Sandusky followed.
"Jerry started pumping his hand full of soap, like he was going to throw it. Matt got out. He went to another shower," the victim testified. Matt appeared nervous, the victim said.
Philadelphia-based lawyer Fortunato Perri Jr., who followed the Sandusky trial, said that he understands how knowing that Matt was set to testify would help give jurors peace of mind.
"Jurors want to feel good about what they did," Perri said. "They work really hard and they want to be sure that when they reach a verdict, they did the right thing. In their minds, the information about the adopted son validated everything."
The victims were extremely believable, said Harper, a Penn State graduate.
"The testimony of the victims was compelling, very compelling," he said. During the 20 hours of deliberations, there were no heated arguments among jurors. They tackled the cases, victim by victim, examining their credibility.
As for the testimony of Sandusky's wife, Dorothy, Harper said, "You know, I think she's in denial. I don't know what was going through her mind, but she just didn't want to believe it. Her testimony was basically meaningless to us."
Harper said that Sandusky should spend the rest of his life in prison.
"When I look at him I don't see remorse," he said. "He didn't seem to have any."
Harper said that he looked at Sandusky the moment before the verdict was read.
"To me," he said, "he looked like a guilty man awaiting his fate."
Sandusky is being held in isolation at the Centre County Correctional Facility in Benner Township while he awaits sentencing on 45 counts of child sex abuse.
Contact Barbara Laker at 215-854-5933 or firstname.lastname@example.org or follow on Twitter @barbaralaker.
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