The nonjury trial for a Delaware County woman accused in the stabbing death of her husband, a former University of Pennsylvania basketball player, began Monday with testimony from a close friend and police.

Matthew White was the starting center on the 1979 Penn team that reached the NCAA Final Four.

At issue is not whether Maria Garcia-Pellon killed White as he lay sleeping in bed at their Nether Providence home. She has admitted the killing to police. The question is whether she is not guilty by reason of insanity or guilty but mentally ill.

"This defendant appreciated right from wrong the night she stabbed him," prosecutor Kathleen McGee said in her opening statements.

Garcia-Pellon, a longtime teacher's aide at a local school, is charged with murder in the first and third degrees and possession of an instrument of crime. She has been found to have schizoaffective disorder, McGee said.

Betty Ann Wilson testified that Garcia-Pellon arrived at her house early Feb 10, 2013, in a disheveled condition and appeared nervous.

Wilson said she knew her friend was not well when she described how the "Republicans in Wallingford had something up in the sky," the Chinese government was involved, and children were in danger.

Garcia-Pellon told Wilson that White, her husband of 25 years, had been watching child pornography.

"That is when she told me she killed Matt," Wilson said.

No evidence of pornography was found on computers in the house, county Detective Michael Jay testified Monday.

Garcia-Pellon, 54, wore red prison scrubs as she sat between her attorneys, Thomas Bergstrom and Kathryn Labrum. Her family and friends sat behind her in the courtroom.

Bergstrom was also the attorney for John E. du Pont, who was found guilty but mentally ill for killing Olympic wrestler David Schultz.

After college, White was drafted by the Portland Trail Blazers of the NBA. He instead played professional basketball in Spain, where he met Garcia-Pellon. He earned an M.B.A. from the Wharton School in 1983 and worked as a technical writer for a software company. The couple had two adult children.

On Feb. 9, 2013, White had taken his wife to the emergency room of an area hospital after her mental health deteriorated. She was discharged with an appointment for follow-up treatment with a psychiatrist the next day. He was stabbed that night.

A tape of detectives' interview with Garcia-Pellon the day of the killing was played in court.

When she spoke of the family cars or work, her voice was strong and clear, but when she was asked about details of the stabbing, Garcia-Pellon's voice faltered or was inaudible.

Jay asked Garcia-Pellon what she told Wilson.

"I killed Matt," she replied.

mschaefer@phillynews.com

610-313-8111 @MariSchaefer