The Unsolved Double Homicide of George Heinrich and Marlene Mazzola

0 comment

Marlene Mazzola, 42, and George J. Heinrich, 59, were brutally murdered in September 1980. The couple had been on their second date earlier in the evening when intruders surprised them upon their return to George’s house.

About George Heinrich and Marlene Mazzola

Billings, Montana stock photo

George J. Heinrich was born in Park City, Montana, on November 24, 1921, to Jacob and Ida Heinrich. He married Margaret Ruckman in 1947. They lived in Ferndale, Washington, Big Timber, Billings, Fox, Fromberg, and Livingston, Montana, where they engaged in farming and ranching. (Findagrave) They had a son, Bradley Wayne Heinrich, b. 3/7/54, and died on 9/24/59, and four surviving children – two daughters and two sons. George and Margaret later divorced.

George was a prominent area cattle buyer and broker who also dipped into the real estate business. He had worked on ranches his whole life and was well-known in the Billings area. 

Marlene Ellen Mazzola was born on March 16, 1938, to Robert J. Sandlin and Lillian E. Wills Sandlin and raised in Butte, Montana. She married Thomas Tahija on August 8, 1957. They had three daughters between 1960 and 1968. Their son, Steven Joseph, died on March 11, 1963, one day after his birth. 

Marlene married John Anthony Mazzola on August 16, 1974, his third marriage. Mazzola ran an auto body shop and was a well-known metal artist in Butte, appearing several times in local newspapers. They had one daughter, Melissa, and later divorced.  Marlene and Mazzola did not have any children together, and they had resided in Butte.  

In August 1979, Marlene became the district manager of District 404 for the direct-selling giant Avon Products. She had been a staff member for the Butte-Silver Bow Chamber of Commerce for six years and had just moved to 2114 Lewis Ave in Billings after separating from her husband in July 1979.  

By the fall of 1980, Marlene was in the process of divorcing Mazzola and was ready to date again. She soon met George, and the two had gone on their first date. But there would be no happy ending for these two after tragedy struck on their second date.

The Murder of George Heinrich and Marlene Mazzola

George Heinrich and Marlene Mazzola: photo of George's home where the killings occurred.
Photo credits: The Billings Gazette

On Saturday, September 20, 1980, Marlene had just returned from a meeting in Denver, and George was anxious to see her again. Both were excited for their second date that evening and looked forward to what the future might hold for them.

George wanted to make the evening special, so he selected choice cuts of meat to barbecue for Marlene that evening. Later, the two watched TV and joined his sister and brother at the Elks Lodge, which was crowded by the time they arrived (Billings Gazette, October 1, 1980). George socialized with his relatives on the dance floor and introduced them to Marlene.

The band stopped playing around 1:30 a.m. on Sunday, September 21, and the couple left the Elks Lodge. They planned to spend the rest of the night alone and drove to George’s home on Old Highway 10 (Highway 312), east of Billings. 

Between 4 a.m. and 4:30 a.m., George’s adopted teenage daughter, Peggy Heinrich, discovered the bodies of her father and Marlene on the floor of George’s bedroom. 

Peggy, now in her 60s, interviewed with Lynne Turner Fitzgerald, and that interview was later uploaded by the Yellowstone County Cold Case Unit. (Hanson, 2023)

“When I walked into the bedroom, my dad was laying facedown on the floor, his hands were behind his back with electrical tape with a pillowcase over his head. And then like I said I never ever got in far enough to see where Marlene was.”

Peggy ran to a neighbor for help. That neighbor drove to the murder scene, checked George’s house, and then called the Yellowstone County Sheriff’s Office at 4:28 a.m.

Murder Investigation

Up close stock photo of a typewriter with "Investigation" typed on white paper

Deputies arrived at the Heinrich home around 5 a.m. and found the front door unlocked with no signs of forced entry. They also discovered George’s keys on the steps outside the door. The intruders had smashed open the bedroom door, and police presumed Marlene and George tried to keep the intruders from entering. 

Police theorized the couple surprised the intruders and ran into the upstairs bedroom, slamming the door behind them. The intruders forcibly entered the room, smashing the door in the process. They then forced the couple to lie down on the floor, tied their hands behind their backs, and placed hoods over their heads. (The Billings Gazette). After strangling them, the intruders fled in Marlene’s car, then later ditched it.

When authorities first viewed the bodies, they were unable to ascertain the cause of death. Both victims were fully dressed, bound with electrical tape, and beaten around their faces. Heinrich’s $16,000 diamond ring and Masonic ring were missing, but around $250 in cash, the proceeds from a recent livestock sale, remained untouched. Also stolen was a 5-inch-tall clock with a gold frame and base and a round white face edged with rhinestones.

Investigators stayed silent on the details of the murders for over a week and quieted local rumors, such as the killers injected the couple with a fatal dose of air. (Thackeray, 1980c.)

Authorities later said while robbery was the most apparent motive, it was not the motive for the execution-style slaying of George and Marlene. (Owens, 1980) They believed George was the target and Marlene was simply at the wrong place and time. Police said the murders likely occurred between 2 a.m. and 4 a.m.

The lack of eyewitnesses, motives, and physical evidence made the case puzzling. However, a witness did see an older model red pickup truck with a missing tailgate going up the lane to the Heinrich residence at around 2 a.m. on the morning of the murders. But they never found the vehicle.

An autopsy later revealed George and Marlene died of asphyxia. Their throat injuries were consistent with strangulation. Neither had suffered a sexual assault. 

Public appeal for car

Photo credits: The Billings Gazette, September 26, 1980

Marlene’s 1979 Pontiac LeMans was found abandoned near Lake Elmo Drive and Main Street early Monday morning, September 22, 1980. George’s white two-door hardtop 1978 Chrysler New Yorker was still parked at his home. Police checked both cars for clues and fingerprints. Police took Marlene’s car to the county shop and later released it to relatives. 

At the end of the week, the police appealed to the public to anyone who had seen either car on the day of their murders but received no leads.

After interviewing over 150 people, investigators narrowed the list to four suspects. However, after further investigation, they ruled out all of them. The case went cold, and not even a $1,000 reward for information brought anything new. It is unclear whether they questioned Mazzola in the murders or where he was at the time. 

Nearly 44 years later, the case remains unsolved.

TCD’s Thoughts

I find this case genuinely heartbreaking. George and Marlene were excited about seeing each other and the prospect of a happy future together. Who wanted George dead and was also cold enough to kill a woman?

Why was Peggy at George’s home at 4 a.m.? Did she live with him? If so, where was she earlier in the night? 

Where was Mazzola? What vehicles did he own? Who were the four suspects they cleared? Was he one of them?

I could not find the exact location of George’s home, so I do not know if it still exists. But it sounds like it was in a rural area, which benefited the killers. I believe there was more than one because both victims were bound first. Robbery was not the motive; this was a personal vendetta. Strangulation is also very personal because you have to get close to your victim. I wish there was information on George’s acquaintances, business colleagues, etc.


“Billings Area Murder Victims Died By Asphyixation — Sheriff.” Great Falls Tribune, October 3, 1980.

“George J. Heinrich.” Online Memorial,

Hanson, Sydney. “Courtship Casualties In The Magic City.” Montana Right Now, August 23, 2023.

“Marlene Ellen (Sandlin) Mazzola.” Online Memorial,

Munzenrider, Rita. “County Files Remain Open on 1980 Double Slaying.” The Billings Gazette, November 4, 1980.

Owens, Dory. “Two Murder Victims Were Asphyxiated.” The Billings Gazette, October 1, 1980.

Thackeray, Lorna. 1980a. “Secrecy Shrouds Slayings.” The Billings Gazette, September 23.

—-1980b. “Murder Probe Under Wraps.” The Billings Gazette, September 24, 1980.

—c. “Sheriff Cools Murder Rumors, Still Not Talking.” The Billings Gazette, September 25, 1980.

—d. “Did You See Cars of Murdered Pair?” The Billings Gazette, September 26, 1980.

“Up to $1,000 Reward Offered For Couple’s Killer.” The Billings Gazette, October 5, 1981.

“George Heinrich and Marlene Mazzola –Billings.” The Billings Gazette, September 15, 2018. (Accessed April 28, 2024)

Leave a Comment

About Me

True Crime Diva

True Crime Diva

I've blogged true crime since 2010, happily taking up only a tiny corner of the internet. I'm not here for attention; I'm here to tell you their stories.

You cannot copy the content of this page!

Skip to content