Believe it or not, there are 1,300 active cold cases in Colorado as of January 2021, according to the Colorado Bureau of Investigation.
Here's a list of some of the most chilling cold cases that have yet to be solved.
1. Dale Williams
In 1999, 42-year-old Dale Williams was an autobody shop owner based in Montrose County, Colorado.
On May 27 of that year, he apparently received a phone call from an unidentified motorist who was stranded around 25 miles from the shop.
What happened next remains a mystery.
Williams didn't return home that night and was reported missing to police the next day.
Six weeks later, his truck was found submerged in a river with the key in the ignition. Dale was not inside.
At one point, William's wife noticed the missing posters she hung at the post office were being torn down. Security footage found that a former friend was responsible, but police ultimately cleared him of having any involvement with Williams' disappearance.
The stranded motorist was never identified and there have not been any significant leads on the case since.
Foul play is suspected.
2. Sharon Marie Copp
In August of 1976, a fisherman at Pueblo Reservoir came across something horrifying—a plastic bag filled with human remains.
Later on the same day, a second bag filled with human remains was found 20 miles away.
An investigation identified the remains as 34-year-old Sharon Marie Copp. Evidence suggests that Copp was beaten and sexually assaulted before being dismembered.
Blunt force trauma was determined to be the official cause of death. Investigators were never able to identify the killer.
3. James Dean Alderton
On a February morning in 1997, a group of mountain lion hunters found the remains of a missing 47-year-old, James Dean Alderton, in Clear Creek County.
"The body was nearly completely skeletonized," according to the Colorado Bureau of Investigation file on the case.
An investigation determined the cause of death to be a gunshot wound and it was ruled a homicide.
The person who killed James Alderton was never identified.
4. Christopher Enoch Abeyta
In July of 1986, Seven-month-old Christopher Enoch Abeyta vanished from his home in Colorado Springs.
Investigators found that the family's garage door opener was stolen and the basement window was open on the night the boy went missing.
Since his disappearance, there has been no viable information on the whereabouts of Christopher Enoch Abeyta.
5. JonBenét Ramsey
The early death of JonBenét Ramsey is one of the most famous true crime stories to ever come out of the state of Colorado.
Six-year-old JonBenét Ramsey went missing from her home in Boulder, Colorado in December of 1996. At the scene, police found a ransom note demanding $118,000 for the girl's safe return.
JonBenét's beaten body was later discovered under a blanket in the family's basement. The child's hands were tied together and there was tape over her mouth. Strangulation was determined to be the cause of death.
The public suspected that Ramsey's parents were responsible for the death early on, but they were formally exonerated of the crime in 2008 by DNA evidence.
In 2006, former teacher John Karr confessed to killing Ramsey, but was ultimately ruled out based on DNA evidence from the scene.
The grizzly nature of the death, coupled with many conspiracy theories, have kept JonBenét Ramsey in headlines ever since.
There have been no credible leads.
6. Lynda Lea Avery
In July of 1997, 35-year-old Lynda Lea Avery was found stabbed to death in the basement of her home in Aurora, Colorado. The investigation also found that Avery's throat had been slashed several times.
At the time of the murder, Avery was living alone and reportedly dating someone named Steve, though no witnesses saw Lynda with any particular person on the night of her death.
Since then, there have been no leads to determine who committed the gruesome crime.
7. Margaret Albo
In 1991, Margaret Albo, 59, was found strangled to death in a vacant parking lot in Denver. She was last seen at a popular restaurant the night before, near where the body was found.
The investigation into her murder quickly went cold and no significant leads pointing to who was responsible for Margaret's untimely death have emerged.
If you have any information that could lead to solving any Colorado cold case, contact the Colorado Bureau of Investigation.
For more information on any of these or other Colorado cold cases, visit the Colorado Bureau of Investigation cold case directory here.
Looking for a podcast about Colorado cold cases? Check out the Colorado Cold Case podcast here.
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