A former Pittsburgh schools psychologist is on trial this week on charges that he sexually assaulted a relative.

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

The victim, who claims he was physically and sexually abused from the ages of 9 to 17, didn't go to the police until 2002, when he was 22 years old. The case has been pending since then.

Assistant District Attorney Jennifer DiGiovanni told the jury that the assaults began when the relative 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.

The defense claims that Mr. Stettner never abused the victim in any way.

"There won't be any evidence to back up what they're saying," defense attorney Tom Pavlinic said.

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