Estimated read time: 6-7 minutes
ROY — Police confirmed to KSL-TV they plan to excavate a possible gravesite in the mountains near Causey Reservoir Wednesday in connection with a 1985 cold case.
"Sheree Warren went missing Oct. 2, 1985. She was a Roy resident at the time she went missing and, as of right now, we've not been able to locate her," Roy Police Sgt. Josh Taylor said.
Police hope to determine whether their planned search site, about 20 miles east of Ogden, holds any evidence related to Warren's presumed murder nearly 40 years ago.
"Hopefully it is significant," Taylor said. "Where this case is so old, anything is significant."
The police effort follows years of investigative work by KSL's COLD podcast into the unsolved disappearance of Sheree Warren. The search for Sheree is detailed in COLD's third season.
Two suspects
Sheree Warren was last seen by a coworker as she left an office building in Salt Lake City. She'd planned to meet her estranged husband, Charles Warren, at a nearby car dealership. It is unclear if Sheree Warren ever made it to the dealership.
Charles Warren later told police he'd called off that rendezvous and instead went jogging in downtown Ogden. Detectives were unable to corroborate this. They also learned Charles Warren and Sheree Warren had been in some heated disputes over alimony and child support in the weeks prior to her disappearance.
Police suspicions of foul play increased six weeks into the investigation when Sheree Warren's car turned up abandoned in the parking lot of a Las Vegas casino. Detectives did not believe Sheree Warren had driven the car to Las Vegas herself.
Charles Warren died in October 2022. He was never cleared as a suspect, but he was never arrested or charged with a crime related to Sheree Warren's disappearance either. This was partly because Charles Warren was not the only suspect. Police also focused attention on an Ogden man named Cary Hartmann during the initial stage of the investigation.
Hartmann, 75, was a former Ogden Police Department reserve officer who'd dated Warren prior to her disappearance. In 1987, a Weber County jury convicted Hartmann on first-degree felony aggravated sexual assault and burglary counts unrelated to the Sheree Warren case.
Hartmann spent 32 years in prison as a result of that conviction. He repeatedly denied any involvement in Warren's disappearance when questioned by a cold case detective and a hearing officer for the Utah Board of Pardons and Parole in 2005.
The Utah Department of Corrections released Hartmann from custody in March 2020.
Causey
Evidence in the Sheree Warren cold case has for decades led police to believe Warren's remains might rest somewhere in the mountains surrounding Causey Reservoir.
On April 4, 1987, Roy police and the Weber County Sheriff's Office received calls from an anonymous man who reported stumbling across the decomposed body of a woman a few miles from Causey Dam. The caller said the body was in a difficult-to-reach area where few people go.
"You have to cross a couple ravines which are about 2 miles, two or three, it's real hard," the anonymous man said according to a transcript of the call.
Searchers attempted multiple times to locate the body using that vague description but were unsuccessful. Police made public appeals, encouraging the anonymous man to call back with additional information, but the caller never responded.
Around the same time, a witness who knew Cary Hartmann personally told police he'd discovered Hartmann trespassing on private property in the mountains near Causey Reservoir on Oct. 6, 1985, four days after Sheree Warren vanished. The witness, an elk hunting guide, reportedly said he was unsure why Hartmann would've been on the mountain at that time.
Detectives also learned in May of 1987 that several of Hartmann's close personal friends owned lots in Causey Estates, a cabin subdivision adjacent to the reservoir. One of those friends told police he'd loaned Hartmann a key to the gate for Causey Estates during the autumn of 1985, just prior to Warren's disappearance.
The Weber County cold case investigator who questioned Hartmann in 2005 asked him about his connections to Causey. In an audio recording of that interview obtained exclusively by COLD, Hartmann denied visiting the Causey area the weekend after Sheree Warren disappeared or having borrowed a key for the gate at Causey Estates.
"No, never, absolutely not," Hartmann said.
The Joyce Yost case
Sheree Warren is not the only Weber County woman missing under suspicious circumstances who might have ended up in the mountains surrounding Causey Reservoir.
In August of 1985, weeks prior to Sheree Warren's disappearance, a man named Douglas Lovell abducted Joyce Yost from her apartment in South Ogden. Lovell had sexually assaulted Yost months prior and plotted to kill her in order to prevent her from testifying at his upcoming rape trial.
Lovell murdered Yost and hid her body. He then enlisted the help of his wife, Rhonda Buttars, to dispose of evidence.
The plot unraveled in 1991 when Buttars confessed her involvement to a South Ogden police detective. The Weber County Attorney's Office granted Buttars immunity in exchange for providing incriminating information about Lovell.
In a recorded interview, Buttars told a detective she'd dropped Lovell off outside Yost's apartment on the night of Yost's murder. The early the next morning, she said Lovell called her from a payphone in Ogden Canyon.
Buttars said she'd later asked Lovell what he'd done with Yost.
"He said he made her drive up the canyon and they went up by Causey," Buttars said. "He just stopped the car and got out of the car and walked up this hill and it wasn't very far off the road. … And he said he didn't bury her very deep."
Prosecutors filed a capital murder charge against Douglas Lovell in 1992. Lovell pleaded guilty to the charge in 1993 as part of an agreement with prosecutors that would spare him the death penalty, so long as he led them to Yost's remains.
In court, Lovell contradicted his ex-wife's assertion he'd taken Yost "up by Causey." He instead directed police to a site along the Old Snowbasin Road near Pineview Reservoir. Extensive searches there during the summer of 1993 failed to turn up any trace of a gravesite or Yost's remains.
A judge sentenced Lovell to die in 1993. Lovell successfully appealed that, leading to a jury trial in March of 2015. A jury once again sentenced Lovell to die at the conclusion of the trial. Lovell appealed and his case is currently before the Utah Supreme Court.
The Joyce Yost case is covered in detail in COLD season 2.
New leads
KSL will continue to follow developments in the Sheree Warren and Joyce Yost cold cases. KSL plans to accompany police as they conduct their search of the site near Causey Reservoir.
Roy Police Sgt. Josh Taylor said the effort shows their investigators have not forgotten about Warren and will actively pursue any new leads.
"If we get tips, we're going to follow up on them until we get closure," Taylor said.
