GLENVIEW (CBS) — A suspected serial killer’s friend and two police investigators are speaking out for the first time, saying they are concerned the mishandling of a local murder case may have let a killer go free to commit more crimes.  

Alleged “Hollywood Ripper” Michael Gargiulo is awaiting trial in California for brutally attacking one woman and killing two others. But California law enforcement officials say they believe Gargiulo’s first victim was Tricia Pacaccio, a teenager from Glenview, Ill., who was brutally stabbed to death in 1993 on the doorstep of her home. 

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“I hope the truth comes out,” said Scott Olson who was friends with Michael Gargiulo. 

Both were high school students, at the time Pacaccio was killed. Olson says he has critical information about the murder but was never allowed to go before a grand jury to say why he believes Gargiulo is the killer.

“There were two sides to Mike — normal person Mike and mad Mike,” Olson said.

He says he and Gargiulo played in a band together and that his friend had a “crazy switch” that Gargiulo’s own parents feared

Gargiulo was never charged with Pacaccio’s murder, but Olson believes somebody dropped the ball in this case. He believes a grand jury should have heard his testimony about Gargiulo’s temper, his weapons and the details of a phone conversation Olson had with Gargiulo the day Pacaccio’s body was discovered.

“He told me he had gone over [to the Pacaccio’s house] when he heard what happened and Mr. Pacaccio actually grabbed him and just started shaking him and said ‘Did you do this, did you do this?'”

Rick Pacaccio, Tricia’s father, said that never happened. But he, too, believes a grand jury should have heard Olson’s phone call story because it shows Gargiulo was lying and possibly covering his tracks about being at the murder scene.

“I couldn’t understand why he would say that, other than maybe to establish maybe his presence on the scene,” said Pacaccio, who thinks Gargiulo was worried his hair or other evidence would be found and he needed to explain it away.

Retired Cook County Sheriff’s investigators Jack Reed and Mark Baldwin also believe this case was mishandled.

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“That would surprise me,” said Mark Baldwin when told law enforcement did not ask Olson about his phone call with Gargiulo, especially since Gargiulo’s DNA was found on Pacaccio’s fingernails.

“There’s people sitting in Statesville on a lot less evidence than what we have now,” said Reed, who along with Baldwin worked the Pacaccio case from 1997 to 2002. They were off the case by the time the DNA was found a year later.

Reed says Olson is one person he would have put before a grand jury. 

“We wanted to put a lot of people before a grand jury and got rebuffed” by the Cook County State’s Attorney’s office, he said.

Law enforcement says the DNA on Pacaccio’s fingernails could have come during a ride Gargiulo and Olson gave Pacaccio days before her murder. But Olson says there was no physical contact.

A Cook County State’s Attorney spokesman says Olson told law enforcement “he did not have a clear recollection if there had been contact between Tricia and Gargiulo.”

The spokesman also says Baldwin and Reed, when they worked the case, wanted to charge a different suspect. The detectives say they believe this other person and Gargiulo were both at the murder scene.  

“The murder of Tricia Pacaccio remains an open investigation and a priority for the Cook County State’s Attorney’s Office as it has been for 17 years,” a Cook County State’s Attorney spokeswoman said in a statement. “The office is and always has been committed to solving this crime and effectively prosecuting the case.”

Meanwhile, the Cook County Sheriff’s Department says California prosecutors asked them to hold off pursuing Gargiulo as a suspect here for the time being.

“The moment we are advised we can proceed, we will resume aggressively pursuing justice for the Pacaccio family. This case is far too important to Tricia’s family and friends and our own department to do anything less,” a sheriff’s office statement read.

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