The same night 15-year-old sophomore Michael Russell was stabbed to death in his South San Jose backyard, the brother of one of the young men accused of killing him for thrills made an unusual discovery.
Corey Thompson had just arrived for a visit at his parents' house on Choctaw Drive on Nov. 10, 2009, when a motion-activated light illuminated some sweatshirts in the driveway, tucked against the front tire of his father's white Bronco.
Figuring someone in the family had been working on the Bronco and forgotten them, he brought the bundle in.
"I tried handing my mom it," he testified Thursday in the murder trial of one of the young men, Jae Williams. His brother Randy Thompson is set to be tried separately later this spring. "But something inside was hitting my leg."
Inside the pockets of the black sweatshirt were one of his mother's kitchen knives and a clean serrated electrician's knife. The kitchen knife was bent and red with blood.
The discovery sparked immediate concern, though the family, unaware of Michael's death at the time, did not call the police that night.
"Shocked," he told the jury, explaining how he, his sister Leslie and parents felt, "that's what we all were."
But Williams, who was also in the house visiting Randy Thompson, offered a ready, albeit chilling, explanation, which the family believed at the time.
"He said he had a psychotic break and used it (the knife) on a cat," Corey Thompson said.
His testimony capped off the first week of Williams' trial, which resumes Monday. In an opening statement earlier this week, prosecutor Valerie McGuire said the evidence against Williams includes DNA and a confession.
Williams, then 15, told police a few days after the slaying that he and Randy Thompson, then 16, planned and carried out the savage attack on Michael " 'cause we wanted to." The duo worshiped Satan and had already beaten a cat to death, he said.
Corey Thompson said that almost immediately after the knife was found, his father, Danny, came home and after conferring privately with his wife, emerged from their bedroom furious.
He ordered Williams out of the house and forbade him from hanging out with Randy, then offered the Santa Teresa High School sophomore some advice.
"He was telling him, 'You should look into getting some help,' " Corey Thompson testified. "Jae was going, 'Hey, yeah, man, OK.' ''
The father then asked Randy Thompson what had happened.
"He said, 'Did you know about this?' " Corey Thompson testified. "Randy was like, 'No, no.' "
The Thompsons did not call Williams' mother about their son's claim he had butchered a cat. Police eventually seized the stained knife, which contained Michael's blood. But it is not yet clear exactly how they found out about it.
According to court documents, Corey's sister Leslie had a friend over that night, Krista Conway, who reported it, apparently after learning Michael had been stabbed at least 12 times.
But Corey also texted his mother about it, according to police records. Thursday, he testified he sent the text after learning of Michael's death. It is unclear whether he knew his brother Randy was a suspect at the time.
"I asked my mother to turn it (the knife) in," he said, "or at least look into it."
Contact Tracey Kaplan at 408-278-3482. Follow her at Twitter.com/tkaplanreport.