Chilling factor behind fatal Colorado Walmart shooting revealed by suspect’s stepsister

Scott Ostrem, 47, center, leaves a hearing in Adams County, Colo., court Friday, Nov. 3, 2017, in Brighton, Colo. Ostrem is being held for investigation of first-degree murder as the suspect in the killing of three shoppers inside a Thornton, Colo., Walmart store Wednesday. (AP Photo/David Zalubowski, Pool)

Last Wednesday in Thornton, Colo., a lone gunman walked into Walmart, opened fire and killed three people. Yesterday, the shooter’s stepsister went public to say that her stepbrother has been hearing voices for the last 30 years.

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Michelle Willoughby, 43, told the Denver Post that Scott Ostrem, 47, experienced a bad acid trip three decades ago after taking 16 doses of LSD. Ostrem now faces first-degree murder and attempted-murder charges.

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Willoughby, now living in Florida, said that Ostrem came home one night after that party in 1988 and that he’s never been the same since.

“When he came home, he was terrified. He had voices in his head. Demons,” she said. “My brother is not this monster. He is not cold blooded. He hears these voices. Honestly, in my heart, I believe there is only so much a person can take.”

“I never thought something like this would happen,” she added.

The family contacted a hospital, and Ostrem underwent a drug intervention but did not get psychological treatment, she said.

The National Institute on Drug Abuse says the long-term effects of LSD and other hallucinogenic drugs can include mood disturbances, paranoia, disorganized thinking and hallucinations. But such effects are rare, the institute said on its website, and they are more likely to occur in people with a history of psychological problems.

There has been some dispute, however, over LSD itself causing Ostrem to hear voices, the Associated Press reported.

Charles Grob, a psychiatry professor at UCLA, said it is unlikely that LSD would be the cause of a decadeslong psychosis. It was more likely that Ostrem had “some severe disturbance to begin with,” he said.

“I don’t think LSD is the right culprit,” Grob said.

Ostrem’s victims have been identified as 52-year-old Pamela Marques, 66-year-old Carlos Moreno and 26-year-old Victor Vasquez.

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The attempted-murder charges against Ostrem alone could result in an eight to 48 year sentence.

The Associated Press contributed to this report.

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