Three booms shattered the night’s silence.

Why was his mother shooting off fireworks in the middle of the night?

Mark Barrett, 9, crawled out of bed in his Rockfield home after the percussive sounds woke him. His mother, Thelma, had been shooting off cherry bombs earlier on that December night in 1971, but it was now after midnight. He remembers being puzzled by the sound.

The boy walked into the home’s kitchen, where he found his mother sitting in the middle of the floor.

He asked her what was wrong.

“Your dad has been shot,” she said.

•••

The murder of Kentucky State Police Trooper William Barrett has gone unsolved for 50 years. It has remained an active investigation that entire time, but it is only in recent years that the case has taken on a new dimension for Mike and Mark Barrett.

Now, the death of their father is not only a bitter memory, it has sparked a renewed desire for elusive justice. The brothers agreed to speak publicly about the case for the first time with the Daily News.

William Barrett, a Tennessee native, was an Air Force veteran and former Tennessee Highway Patrol officer who joined the KSP at Bowling Green’s Post 3 in 1968.

Mike and Mark Barrett attended Rockfield Elementary School, just yards from Morehead Trailer Park’s lot two that they called home.

Mark Barrett remembered that his 6-foot-2, crew-cut father “was always thought of as a big man” and could be “intimidating, but he could be gentle when he wanted to be.”

William Barrett was gone a lot for work but made sure he found time to take his boys to their Little League games.

“We were normal kids with a normal childhood,” Mark Barrett said.

On Dec. 18, 1971, William Barrett was working a routine patrol. When his shift ended at midnight, he headed down Russellville Road to go home.

He parked his cruiser on a concrete pad next to his home shortly after midnight. A sliver of moonlight provided the only light. As he was getting out of his cruiser, someone called his name from near a small shed at the back of the property along a fenced tree line. As Barrett turned, he was hit with a double-barreled shotgun blast. Barrett pulled out his revolver and got a shot off at his attacker.

Before he could fire again, the trooper was hit with another shotgun blast. This time it was fatal. He was 35.

The sound of the gunshots had roused numerous people in the trailer park.

After Mark Barrett was told that his father had been shot, the night’s silence was again pierced by the sound of sirens.

“The next thing I remember, police were everywhere,” Mark Barrett said.

Mike Barrett had also been awakened by the gunshots. When he looked out his bedroom window, he saw his father on the ground next to his KSP cruiser. He tried to make sense of the scene.

“I thought he was working on his car,” Mike Barrett said.

A neighbor soon came to take the boys away from the house. As they left, the boys “passed our dad’s body covered in a sheet,” Mark Barrett said.

Police formed a dragnet that early morning around southcentral Kentucky, stopping any car or driver deemed suspicious. Investigators also honed in on William Barrett’s police work – both in Kentucky and Tennessee – as a likely motive for the ambush.

But after eliminating obvious suspects, the case went cold.

A few months after the murder, Thelma took her boys back home to family in Tennessee and eventually remarried.

“We went on living our lives as best we could,” Mark Barrett said.

The decades passed.

While Mike and Mark knew the case was active and were regularly invited back to Kentucky for memorial events for fallen troopers, the case was more of a memory than a mission.

That changed in 2019.

William Barrett’s murder, and that of another man, Larry Key, was detailed in a four-part series, “The Ambush Killings,” in the Daily News that year. (Visit bgdailynews.com to read those stories.)

Mike Barrett was on vacation in Grand Cayman when his brother sent him a link to the articles.

“It brought back some crazy memories,” Mike Barrett said. “You don’t get over it, you get through it.”

It also shed, for the brothers, new light on the murder of their father.

“My head was spinning” with new details about their father’s case, Mike Barrett said.

It also brought a new desire to see justice.

Through the article, the Barretts also made contact with Renetta Wilson, Larry Key’s widow.

Larry Stinson Key was an Edmonson County native who had married his high school sweetheart, Renetta, in 1960. They had two sons.

On July 28, 1972, Key was driving home from his job at a Cave City truck stop and was turning off Interstate 65 at the Glendale exit. He was being followed by what witnesses later described as a two-tone green car with two men inside. Key stopped his car on the exit ramp and the two men exited the vehicle and approached Key’s car, where witnesses reported hearing shouting.

One of the men then pulled out a .38-caliber handgun and shot Key in the face. The wounded Key jumped out of the car and started running toward I-65. Key was then shot again, with the bullet piercing his heart. He died alongside the exit ramp one day after his 31st birthday.

As in the Barrett case, no one has ever been charged with Key’s murder.

Wilson and her sons believe the murders are linked. According to some sources, Barrett was looking into wrongdoing by others in law enforcement at the time he was killed.

Key, after an arrest on drug charges, was at the same time reportedly cooperating with law enforcement regarding their investigations into criminal activity at truck stops. The activity was allegedly being protected by corrupt police officers like the ones Barrett was investigating.

Law enforcement sources don’t discount the theory that the cases are linked. Confirmation that Barrett was in the thick of investigating criminal activity at truck stops, such as the one Key worked at and was reportedly providing information about, comes in the form of court records that show, for example, that in 1970 he went undercover and purchased amphetamines at a truck stop in Barren County.

Wilson and her sons have offered a substantial reward for information, paid for a billboard spotlighting the cases, established a Facebook page dedicated to the murders and have been investigating the case on their own.

“Her resilience to not let this die down caused us to reevaluate our position,” Mike Barrett said.

The brothers have since been more active in lobbying law enforcement to pursue the case.

They also believe that their father’s murder may be linked to the Key murder and possible law enforcement corruption at the time.

It was only when they read the Daily News articles that they discovered that their father had been working undercover for law enforcement.

In hindsight, “it seemed like he was gone a lot,” Mark Barrett said, but their father never discussed his activities at home.

“It was almost like a double life,” Mike Barrett said.

Over the years, evidence from the cases has gone missing, according to Wilson, and corruption among some in law enforcement at the time has come to light.

“It leads you to believe there was a cover-up at the time,” Mike Barrett said.

As for a resolution after 50 years, Mark Barrett said they are “hopeful but skeptical. … There’s nothing we can do but voice our concerns to the KSP.”

At KSP’s Post 3, Trooper Daniel Priddy said the Barrett case is active, but investigators need help.

“Information is what we need. We hope as time passes on, somebody will come forward,” he said.

Priddy encouraged individuals with any insights into the case to contact the KSP.

“No matter how small it may be … you never know what will help us turn a corner in an investigation,” he said.

Mike and Mark Barrett, who now live in Texas, said looking at their father’s case anew has been difficult, but “by the grace of God and our faith, we have been able to get through this,” Mike Barrett said.

The brothers said even as they seek justice, they have not let anger become the overwhelming emotion when they remember their father.

“We have laid this at God’s feet,” Mark Barrett said.