The California jurors assigned to the complicated, decades-old case involving a man accused of killing college freshman Kristin Smart over 26 years ago, and his father, who is charged with helping to hide her body, will hear more opening statements from defense attorneys on Tuesday who will try to poke holes in prosecutors’ allegations. 

Both Ruben Flores and Paul Flores have pleaded not guilty to allegations related to the disappearance and presumed death of Kristin Smart, who was last seen in May 1996 after a party at California Polytechnic State University, where she was a college freshman.  

Paul Flores, now 45, faces a murder conviction, while his father, 81-year-old Ruben Flores, was charged as an accomplice for allegedly helping his son bury Smart's body. Prosecutors accused the younger Flores of killing the 19-year-old during an attempted rape on May 25, 1996, in his dorm room at Cal Poly, where both were first-year students. His father allegedly helped bury the slain student behind his home in the nearby community of Arroyo Grande and later dug up the remains and moved them.

On Tuesday, jurors are expected to hear an opening statement from Ruben Flores’ defense attorney, Harold Mesick, according to local news station KSBY.com.

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In order of appearance Paul fLORES KRISTIN SMART RUBEN FLORES

This undated photo released by the FBI shows Kristin Smart, the California Polytechnic State University, San Luis Obispo student who disappeared in 1996. ((FBI via AP, File))

During his opening remarks on Monday, Paul Flores’ defense attorney, Robert Sanger, told jurors that if Paul and Smart did interact on campus over that weekend, it was brief and no attempted rape occurred.

Sanger further began to discredit the forensic evidence prosecutors had laid out, particularly the claims by the archaeologist who is expected to testify that the stain underneath Ruben Flores’ deck is the result of a body, the San Luis Obispo Tribune reported.

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Paul Flores had long been considered a suspect in the killing, but prosecutors only arrested him and his father in 2021 after the investigation was revived.

Paul Flores man accused of murdering Kristin Smart

Paul Flores stands during his murder trial in Monterey County Superior Court in Salinas, Calif., Monday, July 18, 2022.  (Daniel Dreifuss/Monterey County Weekly via AP, Pool)

Cadaver dogs used in the search are unreliable, Sanger said, and the profession itself is not regulated. He said handlers certify each other, and there is not a government agency that oversees them. He also said handlers are volunteers, not scientists, like the witness he plans to call.

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"I don’t want to demean these volunteers, they are very helpful," Sanger said. "They specialize in disaster, finding bodies — that’s what they’re good at and bless their hearts they’re out there helping people, but from a forensic science standpoint, you’ll hear that it’s nothing other than a clue."

Sanger previously said the evidence remained the same as it did in the 1990s when Paul Flores was the prime suspect but never charged with a crime.

Judge overseeing Kristin Smart murder case

Judge Jennifer O'Keefe listens during opening arguments of the Paul Flores murder trial in Monterey County Superior Court in Salinas, Calif., Monday, July 18, 2022.  (Daniel Dreifuss/Monterey County Weekly via AP, Pool)

"The evidence then and now is based on speculation and not proof of facts," Sanger said in court documents.

Sanger has tried to pin the killing on someone else — noting that Scott Peterson, who was later convicted at a sensational trial of killing his pregnant wife and the fetus she was carrying — was also a Cal Poly student at the time.

Trial Judge Jennifer O’Keefe — who is a year younger than Kristin Smart would be today — however, has barred suggestions of alternate suspects unless Sanger can provide evidence of their direct involvement.

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Ruben Flores in court Kristin Smart trial

Ruben Flores, father of Paul Flores, sits in court Monday, Aug. 2, 2021, in San Luis Obispo, Calif. (David Middlecamp/The Tribune (of San Luis Obispo) via AP, Pool,File)

Paul Flores was the last person seen with Smart on May 25, 1996, as he walked her home from an off-campus party where she got intoxicated.

He downplayed his interactions with her when he first spoke with police three days later, saying she walked to her dorm under her own power, though other witnesses said that she had passed out earlier in the night and Flores helped hold her up as they walked back to campus.

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Flores had a black eye when investigators interviewed him. He told them he got it playing basketball with friends, who denied his account, according to court records. He later changed his story to say he bumped his head while working on his car.

Investigators have conducted dozens of searches over two decades, but turned their attention in the past two years to Ruben Flores' home about 12 miles south of Cal Poly in the community of Arroyo Grande.

Behind lattice work beneath the deck of his large house on a dead end street off Tally Ho Road, archeologists working for police in March 2021 found a soil disturbance about the size of a casket and the presence of human blood, prosecutors said. The blood was too degraded to extract a DNA sample.

Smart’s remains have never been found and the mystery of how she vanished from the scenic campus tucked against a verdant coastal mountain range is likely to be central to the trial.

Ruben and Paul Flores in court Kristin Smart trial

In this April 15, 2021, file photo defendants Paul Flores, top left, and his father, Ruben Flores, bottom right, appear via video conference during their arraignment in San Luis Obispo Superior Court in San Luis Obispo, Calif.  (AP Photo/Nic Coury, File)

At a preliminary hearing last year, prosecutors presented evidence that four cadaver dogs stopped at Flores’ room and alerted to the scent of death near his bed.

Prior to trial, the case was moved 110 miles north to the small city of Salinas.

Earlier in the day on Monday, Deputy District Attorney Christopher Peuvrelle described how Smart disappeared from California Polytechnic State University over Memorial Day weekend in 1996, the San Luis Obispo Tribune reported.

"In 1995, Stan and Denise Smart sent their oldest daughter Kristin to Cal Poly in San Luis Obispo," Peuvrelle said in his opening remarks. "During her freshman year they looked forward every Sunday to a phone call from her — it was their ritual."

That weekend, the call never came, Peuvrelle told jurors.

"And while the entire community banded together to search for Kristin desperately, Paul and Ruben Flores did not join in," Peuvrelle said to the jury. "You will hear Ruben Flores would tear down missing posters of Kristin — tore down her smiling, beautiful face — called her a ‘dirty slut,’ all while her corpse was decomposing underneath his deck."

kristin smart disappeared in 1996

Sept. 7, 2016: A sign outside the James R. Murphy, Jr. law office in Arroyo Grande, Calif., offers a reward for information in the 1996 disappearance of Kristin Smart. (AP)

Peuvrelle played for jurors part of a phone call between Paul Flores and his mother, Susan, in which she tells him she needs him to start listening to a podcast, called "Your Own Backyard" – which has been credited with reviving interest in the case – and telling her son: "I need you to poke holes in it where you can," according to KSBY.

But Sanger reportedly brushed off the recording as being a snippet of a 27-minute conversation. He reportedly told jurors that it would be expected that a mother would want her son to look for false information in a podcast about a case in which her son is accused. 

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Separate juries were selected from a pool of more than 1,500 Monterey County residents to weigh the evidence against each defendant. The trial is expected to last about four months.

The Associated Press contributed to this report.