Dateline: Unforgettable explores John Scandoval's crime in detail when he murdered his wife on October 19, 1995. John and Tina had met in a nursing school, and got married in 1992. Their marriage took a dark turn with John's growing obsession and controlling behavior towards his wife. Tina was at the time 23 years old and was last seen going to meet John to finalize her separation, and she was never seen after that. The family and prosecutors were sure about John being the one behind her disappearance, but even after 22 years of the crime, the authorities didn't have any substantial proof to charge John.
A major development in the case occurred in 2009 when the case was reopened. It was discovered that Tina's disappearance isn't just the only crime of John. He was a serial peeping Tom who was caught with 2 portraits of Tina and over 100 recordings of random women in their personal spaces. Though this gave the prosecutors enough evidence to charge John, Tina's body was still missing.
Read on to know the complete details about how the police caught John Sandoval in connection with her wife's murder.
Dateline: Unforgettable- How did the police catch John Sandoval in connection with her wife's murder?

Tina and John got married in 1992, and it was no less than a fairy tale. However, immediately after that, Tina began to feel suffocated by John's over-obsessive and controlling behavior. Tina was living separately from her husband, especially when she got to know about his voyeuristic, creepy behavior, as she was worried about her safety.
On October 19, 1995, when Tina failed to return home or call her sister, her family went to the Greeley Police Department. The detectives recognized John's name immediately, given his track record. He was by then known locally as a serial Peeping Tom, as shown on the Dateline episode.
The investigation began, and they first traced John, who had returned home early morning at 4:45 am, having been outside the entire night. When detectives entered the house, John was in the shower, while his car had a wet shovel, a rope, and pail, a flashlight on a lanyard, and several of Tina's credit cards in the home.
All of this hinted towards a late-night burial, but without body evidence or a confession, the prosecutors were unable to charge him with anything.
In 2009, a major development happened when John was finally convicted, as per Dateline

Tina’s family never stopped searching. In 2009, a new district attorney decided to reopen the cold case, giving detectives another chance to go after John. John was released after spending 4 years in jail for a trespassing charge and was living in Las Vegas. When the authorities combed his new apartment, they found 2 portraits of Tina and over 100 VHS tapes and 70 minutes of tapes showing John secretly filming women. He also sexually assaulted one of the women on camera while she was sleeping in her hotel room.
This strengthened the case against him in Tina's disappearance, and he was charged with first-degree murder. However, in 2016, the conviction was overturned because of a lack of evidence. That is when John confessed to his crime in exchange for a reduced term and charges. Tina's family was desperate for closure and agreed to the same, as John told them that he would reveal the whereabouts of Tina's body.
Justice was served at last, and John was imprisoned for 25 years, as per Dateline
John led the investigators to the Sunset Memorial Gardens Cemetery in Greeley, the same cemetery where he once worked part-time. There, beneath a World War 2 veteran's grave, was buried Tina's body, remaining hidden for 22 years.
“We finally knew where she was,” her sister Susan said. “But he’ll never tell us why. That’s the control he still keeps.”
John had used his insider knowledge of burial schedules to hide her body in an open grave that was to be filled the next day.
In exchange for his cooperation, John Sandoval pleaded guilty to second-degree murder and received a 25-year prison sentence, as shown on Dateline. His next parole hearing is set for 2026, and the family is determined to keep him behind bars after what he has done to them.