Families, investigators continue to search for answers in 5 college student cases

On Saturday, May 25, 1996, Kristin Smart, a freshman at Cal Poly State University, walked home from a party at 2 a.m. and was never seen again. She was 19 years old.

An arrest would not be made for 25 years.

"20/20" took a fresh look into why the investigation into Smart's disappearance began slowly, in an episode now streaming on Hulu that features interviews from investigators and family members. But not all unsolved cases involving college students end in arrest.

ABC News took a look at Smart's case and four other cases below.

1996: Kristin Smart

The investigation into Kristin Smart's disappearance had complications – Smart's body was never found, false sightings were reported, and the last person to see her alive stopped cooperating with authorities. But the investigation into Smart's disappearance, as San Luis Obispo Sheriff Ian Parkinson told ABC News, "began very slowly."

Smart's roommate, Crystal Calvin, noted Smart hadn't returned home on May 25, 1996, and alerted campus officials. Calvin told ABC News, Cal Poly felt "very safe" and described how the Cal Poly University Police Department told her they were "sure...she'll be back" after Memorial Day weekend.

On Tuesday, Smart didn't show up to class and Calvin told ABC she and her friends tried to report her as missing to the San Luis Obispo Police Department – the local police. They referred her back to the Cal Poly campus police.

Campus police began interviews that day -- four days after Smart's disappearance and outside the critical first 72 hours in a missing person's case.

As campus police continued their investigation, they spoke several times with Cal Poly freshman Paul Flores, who walked Smart home after the party on May 25. Even though he was the last person to see her alive, Sheriff Parkinson said there was still "a lack of physical evidence," tying Flores to the case.

A month after Smart's disappearance, due to "family's pressure," Parkinson said the university police reached out to the San Luis Obispo County Sheriff's Office to request that they "step in and take over the investigation."

By then Flores and his roommate had moved out of the dorm and a cleaning crew had come through, Detective Clint Cole, who worked on the case for the San Luis Obispo Sheriff's Office, told "20/20".

Though the room was empty, four cadaver dogs separately alerted to the smell of human decomposition on Flores' mattress, which later was a key piece of circumstantial evidence.

Although Cole said the case "was always active," it was 27 years before a resolution. In March 2023, Paul Flores was sentenced to 25 years to life in prison for the murder of Kristin Smart.

Despite Flores' conviction, Smart's father, Stan Smart, said in a presser that her family "were not happy" because Smart's remains had never been found. "From that aspect, we don't have closure," he said.

1969: Betsy Aardsma

Betsy Aardsma was 22 years old when she was found under a pile of books in the stacks of Penn State University's Pattee Library on November 29, 1969, according to the Pennsylvania State Police.

The first-semester graduate student was transported to the hospital where she was declared dead. There was little blood at the scene, so the initial response did not treat the incident as a homicide.

But at the hospital, it was revealed that the manner of death was a stab wound to the chest.

By the time Pennsylvania State Police responded to the incident, the body had been removed and the area was being cleaned – complicating the homicide investigation.

According to police, a witness said they saw a man leaving the area where Aardsma was found and a composite sketch was made. The Pennsylvania State Police confirmed to ABC News that the case remains open.

Anyone with information should contact the Pennsylvania State Police Troop G Cold Case Department at 814-696-6158.

1986: Jane Marie Prichard

University of Maryland graduate student Jane Prichard was last known to be conducting botany experiments in Blackbird Forest State Park, according to the New Castle County Police Department.

Her body was found partially unclothed by two campers on September 20, 1986 near her equipment, as reported by The Washington Post reported.

She was killed by a shotgun blast from behind, New Castle County Police Department confirmed, and a squirrel hunter came forward to police to report that, before her estimated death, he saw both Prichard and another hunter near her.

Investigators arrested the squirrel hunter who came forward with the tip in October 1986 and charged him with Prichard's murder, The Washington Post. A hair at the scene underwent DNA testing – still in its infancy – and it was not a match to the man police arrested, which cleared him.

Charges were dropped in August 1987 and no other suspects have been named, according to the New Castle County Police Department. The authorities tell ABC News that the evidence in the case is still under review using modern DNA testing technology.

Anyone with information should contact the New Castle County Cold Case Homicide Squad at 302-395-8130 or Delaware Crime Stoppers at 302-739-5927.

1998: Suzanne Jovin

Thirty minutes after she was last seen on Yale University's campus, senior Suzanne Jovin was found stabbed 17 times in a park almost two miles away.

"20/20" covered the story in March 2000. At the time, investigators failed to recover a weapon and little physical evidence surfaced. Sources close to the case reported that investigators from the New Haven Police Department developed a roughly 20-person "pool of suspects." But the name of one suspect, Jovin's senior thesis adviser, leaked to the press.

In an interview with "20/20" , that thesis adviser maintained his innocence and blamed both Yale and the New Haven Police Department for rushing to presume his guilt. Jovin's family and friends meanwhile told "20/20" about frustrations Jovin allegedly had with her adviser before her death. In his interview, her advisor claimed that he never saw Jovin outside of class and had never argued with her.

Jovin’s advisor reached a settlement with the city and the university in 2013 over claims that they damaged his career and reputation by circulating his name as a suspect. At the time, both the university and the New Haven Police Department denied any wrongdoing. In the wake of the settlement, New Haven State’s Attorney Michael Dearington revealed in an interview with the New York Times that Jovin’s advisor was no longer a suspect.

Attorney David Grudberg, who represented Jovin’s advisor, told ABC News that investigators have not publicly admitted wrongdoing in the years following the settlement.

In a statement to ABC News, the spokesperson for the Chief State's Attorney's Office at the Division of Criminal Justice wrote that the investigation into the case remains “very active.” The spokesperson did not confirm if, or how many, suspects are related to the case currently and if any new evidence has been unearthed in recent years.

Twenty-five years later, Jovin's murder remains unsolved.

Anyone with information should contact the Jovin Investigation Team Tip Line at 866-623-8058

2002: Josh Guimond

Josh Guimond was at a party about three minutes from his dorm when he went missing on November 9, 2002, in Collegeville, Minnesota. The 19-year-old St. John's University student left a card game around midnight to use the bathroom, but never returned, ABC News reported at the time.

Investigators from the Stearns County Sheriff's Office initially considered the theory that Guimond fell into a body of water and drowned after a K9 dog tracked his scent to a shore, Investigator Andrew Struffert from the Stearns County Sheriff’s Office told ABC. Despite multiple dives in May 2003 in the area, Guimond’s body was never found.

In 2002, ABC News reported on the similarity between Guimond's disappearance and that of two other missing college-aged men – Christopher Jenkins and Michael Noll – who all went missing within 10 days and 170 miles of one another. Jenkins' body was found in a river in 2003 and the Minneapolis Police Department reclassified his death as a homicide in 2006, according to Minnesota Public Radio News. Noll’s body was recovered from a lake in 2003 and the final autopsy indicated that he died from a probably freshwater drowning and not foul play, the Eau Claire Police Department confirmed.

The Stearns County Sheriff’s Office tells ABC News that the investigation into Guimond’s disappearance is active. The case is still classified as a missing persons investigation.

Anyone with information should contact the Stearns County Sheriff's Office at 320-259-3700.

Editor's Note: This story has been updated.