The prosecutor described to the jury a childhood filled with abuse, isolation, molestation and horror.

The victim, who says he was abused from the ages of 9 to 17, is now a grown man. At 29 years old -- seven years after he went to the police --he is expected to testify against the defendant.

But attorneys for former Pittsburgh schools psychologist Donald Stettner said there was never any abuse of the alleged victim -- a relative of Mr. Stettner -- and that instead the case revolves around two dysfunctional people and made-up allegations.

Mr. Stettner, 53, is charged with involuntary deviate sexual intercourse, criminal conspiracy and endangering the welfare of children from 1991 to 1998.

Assistant District Attorney Jennifer DiGiovanni said during opening statements that the assaults began when the victim was living with his mother.

"The defendant began to systematically assault [him]," Ms. DiGiovanni said. "[His] mother was completely unwilling to stop what was happening. She did absolutely nothing to protect him."

His mother pleaded guilty in March 2009 to indecent assault, corruption of minors and endangering the welfare of children.

She is testifying in the case against Mr. Stettner.

According to the prosecution, just before the victim was to testify at Mr. Stettner's preliminary hearing in March 2003, he received a packet that he believed was blackmail.

It included notes from other relatives that said Mr. Stettner was sorry, as well as a post-dated check for $25,000 and a promissory note for $50,000.

"Instead of taking that bribe [the victim] took that whole packet and gave it to the authorities," Ms. DiGiovanni said.

But defense attorney Tom Pavlinic painted the packet as a much more innocent gesture.

The victim and Mr. Stettner had previously talked about going into business together. When that venture didn't get off the ground, Mr. Pavlinic said, the victim got mad and made up the allegations against his client.

The packet, including the check and promissory note, were just a way Mr. Stettner and his family thought they could resolve the entire situation, the lawyer said.

Mr. Pavlinic told the jury during his opening statement that there was no evidence the victim was abused. Instead, the boy enjoyed good grades, participated in sports, had good relationships with his family and friends and was a role model for others.

"There's not one scrap of medical evidence in any of [the victim's] medical records to establish physical abuse," Mr. Pavlinic said.

In preparing for trial, the defense asked the victim to undergo a physical examination to determine if he had any effects from what prosecutors have said were hundreds of instances of anal penetration over that several-year period, but the man refused, Mr. Pavlinic said.

"There won't be any evidence to back up what they're saying," he said.

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