Prosecutors Think Paul Flores Tried to Rape Kristin Smart in Dorm Room Before Killing Her
Paul Flores is accused of murdering Kristin Smart in 1996
A press release from San Luis Obispo County District Attorney Dan Dow states, "It is alleged he caused Kristin's death while in the commission of or attempt to commit rape."
The press release also alleges that Flores' father, Ruben Flores, "helped conceal Kristin's body after the murder was committed."
At a Wednesday press conference, Dow said, "Significant new information has come into the sheriff's office over the last two years and some very important information just a month ago."
Dow said Paul Flores, 44, has been charged with first-degree murder in the presumed 1996 killing of Smart, then a 19-year-old California Polytechnic State University, San Luis Obispo student who disappeared without a trace on May 24 of that year after attending an off-campus party.
Ruben Flores, 80, is charged with accessory after the fact to the crime of murder.
Paul Flores' attorney Robert Sanger tells PEOPLE that he doesn't comment on pending cases, adding, "We will do our talking in court."
Ruben's attorney Harold Mesick says his client will enter a plea of not guilty at an arraignment scheduled for Thursday.
"I disagree with the district attorney," he tells PEOPLE. "I don't believe there is any evidence, especially objective physical evidence, that my client has committed any crime. I don't think they have sufficient evidence to prove my client has done anything wrong."
The criminal complaint against Paul Flores states that prosecutors intend to "admit evidence of prior sexual acts" in the case.
With classes finished before the long Memorial Day weekend, Smart called her parents on Friday, May 24, 1996, and left a message telling them that she and some friends were heading to a party at 8 p.m. that night. While she told her parents to call her before she left, she never spoke to them.
Smart ended up attending an off-campus party, where she became intoxicated and passed out on a neighbor's lawn, according to witnesses.
Paul Flores, Smart's former university classmate, was the last known person to see her alive after volunteering to walk her home in her inebriated state from the party, police have said.
Dow said Flores killed Smart in his dorm room.
"We certainly believe Mr. Flores' dorm room was a crime scene," he said.
No one ever saw Smart again. Police questioned Flores but over the years he was never charged and remained mum about the case, invoking his Fifth Amendment right to remain silent when he was deposed in a 2005 wrongful death civil suit brought against him by Smart's parents, which they subsequently dropped.
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During the press conference, Dow said investigators are looking into whether Flores sexually assaulted other women in the Los Angeles' neighborhood of San Pedro where he has been living since 2005.
He urged the public to come forward with information.
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