For 20 years, the family of onetime Cal Poly student Kristin Smart has had no closure in her disappearance and presumed murder, and now the FBI and the San Luis Obispo Sheriff's Department have begun excavating sites on the campus in a new search for her remains. As CBS News reports, just as the fall semester is kicking off, a team began digging a three-foot-deep trench in a hilly area near a parking lot at the edge of the campus where Smart was last seen on Memorial Day Weekend in 1996. The sites, identified by cadaver dogs specifically trained to seek out very old human remains, were selected back in January as part of an ongoing reopening of Smart's case.

As the LA Times is reporting, the dig is especially conspicuous because, "The search is centered on the giant 'P' in a hillside sign that stands for Cal Poly." There are three dig sites altogether, and ABC News actually explains in the video below that the excavation is happening on the other side of the hill where the iconic "P" is painted.

Smart's case made national news at the time, and despite a massive search effort involving ground-penetrating radar, helicopters, and an army of volunteers, as well as continuing reviews of the case up through this year, her remains were never found and no one was ever charged in the case. The 19-year-old from Stockton went missing after leaving a party at an off-campus house at 2 a.m. on May 25, 1996. Tim Davis, a senior who had helped throw the party, discovered Smart passed out on a neighbor's lawn and along with Cheryl Anderson, another partygoer, escorted her back toward her dorm, Muir Hall. They were quickly joined by a fourth student who had been at the party, 19-year-old Paul Flores, who offered to take Smart the final part of the way because his dorm, Santa Lucia Hall, was in the same direction as hers on what's called Poly Hill. Anderson and Davis left Smart with Flores to go their separate ways, and Flores claims that he stopped at his dorm and let Smart walk by herself back to Muir Hall, but he was the last person known to have seen her alive.

While Flores is not mentioned by name by San Luis Obispo County Sheriff Ian Parkinson, it's clear Parkinson is referring to him when he tells CBS News, "I would say it’s safe to say he's [still] a person of interest in the case."

There may be other suspects or persons of interest as well, and notoriously, convicted wife-murderer Scott Peterson was questioned and cleared in Smart's disappearance, because he was in fact a student at Cal Poly at the same time, and graduated in 1997.

Campus police were blamed at the time for not alerting outside authorities to Smart's disappearance or initiating a search soon enough because they believed Smart may have gone camping for the holiday weekend, which delayed them several days. This prompted the state legislature to pass the Kristin Smart Campus Safety Act of 1998, which sets clear guidelines for when campus police must call in outside authorities to investigate a violent crime.

As the LA Times recalls, Flores has flatly denied every allegation against him after being sued in civil court by the Smart family. He only once came close to incriminating himself in an initial interview with San Luis Obispo County district attorney’s officials, when he "pulled his arms into his T-shirt, scrunched over at the waist in his chair and lifted his feet off the floor, as if moving toward a fetal position" and said, "If you are so smart, then tell me where the body is."

The latest lead came after the three cadaver dogs, two Springer spaniels and a German shepard mix trained on Civil War battlegrounds and sensitive to the scent of human decomposition, honed in on three sites on this hillside, where digging begins in earnest today.

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