(CBS4) – There are some wounds that never heal. One of those is losing a father.

“There’s probably not a single day that we don’t think about him,” said Sheila Carpenter Barela.

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Almost 50 years ago, on Dec. 27, 1973, Colorado State Troopers visited Sheila’s childhood home. They were there with news about her father — Thomas Carpenter — to give his wife.

(credit: Rocky Mountain News)

“I recall her saying ‘He’s dead isn’t he?’” Sheila told CBS4.

It left a hole in their family that will never be filled.

“He has grandchildren and great grandchildren and none of them ever had any type of relationship with him,” Sheila said.

Thomas was a state trooper. He was working the Interstate 25 corridor just north of Denver. He stopped a car that turned out to be stolen. That’s when he was ambushed by two men.

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Thomas Carpenter (credit: Denver)

“I think one of them walked up in front of them, walked up behind him and that’s what they did, they wrestled him to the ground, took his gun and forced him to drive away,” said Ken Sniff, a former Colorado State trooper and friend of Thomas.

The two men, one white and one Black, forced Thomas to drive to Denver’s Montbello neighborhood. They stopped in the parking lot of some apartments, then did the unthinkable.

“He was murdered. He was shot four times in the back of the head,” said Col. Matt Packard of the Colorado State Patrol.

(credit: Denver)

The suspects have never been caught. The only break in the case Denver police has had over the years is Thomas’ gun was found in New Mexico for some reason. Other than that, the case has gone cold.

Now, they are asking for help solving the case so they can give the Carpenter family some type of closure.

“Forty seven years later I hope and pray all the time that there will be some resolution and with that possibly justice,” said Cory Carpenter, Thomas’s son.

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If you remember this crime or have any information, call Crime Stoppers at 720-913-7867.

Michael Abeyta