Nearly 18 years ago, when she was 13, JoAnn “Holly” McGuire Campbell was at a party where three people were shot and killed and a fourth was wounded. She identified 15-year-old Jason Gray as the shooter, and her testimony was key to his conviction.

In March the judge granted Gray a new trial, and if the prosecutors’ appeal fails, Holly might well be back on the stand. If so, it’s likely the case will again turn on whether the jury believes she saw what she says she saw.

Joanne Lewis, an adult who’d been visiting with the older Bodencaks upstairs but had gone downstairs to listen to the music, would later testify that she saw three bodies on the floor. She ripped open the shirt of 16-year-old Michael Villasenor, who had a bullet hole in the left side of his chest. “I tried to put my hand in there,” she told the court, “and the blood started squirting through my fingers. So I started giving him mouth to mouth, and his eyes rolled back in his head, and saliva came out of his mouth. He gave one big ‘Ugh,’ and that was it.” Lewis closed his eyes and laid a leather jacket over his head.

Gray was born in Saint Louis to Nellie LaGrand and Van Gray, a truck driver who was married to someone else. “This was one of those deals when my wife and I were having problems, and I was out running around,” says Van, who lost contact with his son after LaGrand moved to Chicago when Jason was still young. LaGrand, who survived on public assistance and babysitting money, had ten children by three different fathers, and Gray was the third youngest.

Detectives at Area Three questioned Gray soon after he arrived. At first he said he’d been at Burgos’s apartment all night, partying and then babysitting the son of her roommate, and he insisted he’d never left. But then Holly McGuire picked him out of the lineup.

But the evidence against Gray was mounting. Other kids put him at or near the murder scene. Jesse Alvarez, a member of the Two Twos, picked Gray and Manuel Bobe–a 15-year-old who was, like Gray, a member of the Two-Sixers–out of a lineup as two of the people in the doorway, and he identified Gray as the shooter. Bobe, who’d told police he was standing in the backyard of the Washtenaw house, also fingered Gray. The police report states, “Bobe saw a white male known to him as Jason Gray and three other males standing at the back basement door. All had guns and Bobe saw Jason firing into the basement.”

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Gray and Bobe were charged with three counts of murder and one of attempted murder. Both were taken to the Audy Home. Gray, who says he didn’t know Bobe, remembers asking him about the statement he’d made. He says Bobe muttered, “I’m scared.”