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Dennis and Merna Koula were a beloved couple on the verge of retirement when they were found shot execution style in their Wisconsin home.
Myrna, a 65-year-old substitute teacher, was shot in the back of the head as she was typing at the computer in the family’s office. Her husband, Dennis, a well-liked local pharmacy owner, was gunned down shortly after he had returned home in May of 2010.
“He was holding his car keys in one hand. He had his coat on, so it was clear that he had just walked in the door,” La Crosse County Sheriff Steve Helgeson told “An Unexpected Killer,” airing Sundays at 6/5c on Oxygen. “He hadn’t even set everything on the counter yet.”
The couple, who had been doting parents and grandparents, had been happily married for 42 years before their lives were violently cut short in what Helgeson described as an ambush.
“When I heard about it, I thought I can’t believe this was happening. I was devastated,” family friend Helen Van Roo said. “It hit me real hard. I was like, why would somebody kill them? Everybody loved them.”
The bodies were discovered by the couple’s adult son Eric, who had gone to check on his parents after he received a call from his mother’s school saying she hadn’t show up for work.
“I am at my mom and dad’s house. I came to check on them and my dad’s on the floor,” Eric said in a frantic call to 911.
There were no signs of forced entry in the home and although the drawers of a dresser in an upstairs bedroom had been opened, it looked like it had been staged by the killer to look like a burglary. Myrna’s purse was still in the house and Dennis’ wallet was still tucked in his pocket.
“It just seemed to make no sense,” Helgeson said of the shocking shootings. “We’re trying to understand who would do that and what would be the motive?”
Investigators initially believed it may have been a case of mistaken identity after one of the couple’s neighbors told them he was concerned it may have been a hit meant for him.
The man told investigators that as a banker he had been getting threats as a result of the spiraling economy at the time. The most recent threat had been just a few days earlier.
“He was very concerned,” Helgeson said. “He believed that his life was in danger. He felt that he may be next.”
The man’s fears only deepened when he realized a search of his address on Google maps mistakenly identified it as the Koula home.
“He thought that the killer had killed the wrong people,” said Kurt Papenfuss, a captain with La Crosse County Sheriff’s Department.
Yet, when authorities got back the autopsy report they learned that the Koulas had been killed days before their bodies were discovered, putting their deaths before the neighbor ever received that threatening phone call.
"The timeline, it just didn’t make any sense,” Papenfuss said.
Using data gathered from the computer Merna had been using at the time of her death, authorities were able to determine that she had been killed around 5:41 p.m. on a Friday.
After ruling out the neighbor’s theory, investigators decided to take a look closer to home and spoke with both of the couple’s children. Eric, a day trader, had been extremely emotional over the sudden deaths of his parents but had also been willing to help investigators in any way that he could.
“Dennis and Eric were pretty close, some people would say like bread and butter,” Van Roo said. “They always talked. They’d have get togethers all the time.”
On the day his parents were killed, Eric told investigators he had worked until 2 p.m., then went over to a friend’s house to work on a bathroom renovation before going to two stores to buy his wife a specific type of plant for an anniversary gift around 5:30 p.m. Shortly after purchasing the gift at 6:15 p.m., he went out to celebrate his anniversary with his wife and some friends.
During the questioning, Eric did provide one other possible clue. He said that his sister Cindy and husband Pat had been receiving money from his parents for years and they had just told her they planned to cut her off the morning of the murders.
“Cindy relied on her parents. They needed this money to pay their bills,” La Crosse reporter Jenna Bourne said. “When Dennis had told Cindy that he was cutting her off, she didn’t know how those bills were going to get paid.”
Investigators learned that both of the children stood to inherit around $700K after their parents’ deaths.
“Me and Dennis would talk about Cindy at the pharmacy and he kept telling me that he was sick and tired of supporting her every month,” Van Roo said.
Police called Cindy, who worked at a local collections agency, in for questioning. She admitted to being the “black sheep” of the family and told detectives that she believed her parents had always treated Eric as the favored child, but adamantly denied having anything to do with their deaths.
At the time of the murders, Cindy had been at work until 4:45 p.m., stopped at the store and purchased beer and ice around 5:30 p.m. and then had a barbecue with the neighbors that night.
Investigators also took a close look at Cindy’s husband, Patrick, who had been unemployed.
“Family and friends said that Patrick did not get along with Dennis and Merna and Patrick stood to inherit a substantial amount of money along with Cindy,” Helgeson said.
The morning of the murders Cindy had told her husband that Dennis and Merna had decided to cut them off financially. Investigators also learned that Patrick could be violent when he drank alcohol and was a former Marine, who knew how to handle weapons.
Patrick admitted he wasn’t well liked by his wife’s parents, but he insisted that at the time of the murders he had been at home playing video games. His X-Box gaming console later confirmed his alibi.
One week after the murders, Dennis and Merna’s son Eric told police he got a disturbing note in the mail that said “fixed you” and was worried he could be the next target.
“The handwriting looked like it could have been done by someone very young. It was so strange,” Helgeson said. “It was probably written that way so a handwriting analysis couldn’t be done.”
Investigators got the surprising break in the case that they needed after subpoenaing Dennis and Myrna’s bank records. They learned that Cindy wasn’t the only child the couple had been supporting. Dennis and Merna had also been secretly giving large amounts of money to their son Eric.
Strangely, Eric had also cashed a check for $50,000 from his parents after the murders. Investigators would ultimately determine the check’s signature had been forged by Eric.
“He told everybody that he was extremely successful with his day trading, but what we found out was Eric was broke,” Helgeson said, adding that Eric had even kept the secret from his own wife.
Detectives also learned that at the same time they had stopped financially supporting Cindy, they had also stopped supporting Eric, giving their son a motive for murder.
Their suspicions wee confirmed when they dig deeper into his alibi. They learned that Eric had actually left his friend’s home earlier than he had told investigators. They also only found evidence that Eric had gone to one store — not two — to purchase the plant for his wife.
“There was a window of opportunity for Eric to commit the murders,” Papenfuss said.
They were also able to tie the “fixed you” note to Eric himself through the envelope, which matched others found inside his home.
“He’s as cold-blooded as a murder-for-hire man. His parents did nothing but love him and take care of him his whole life,” Papenfuss said of the shocking killer.
Eric was arrested and convicted in 2012 of the murders of his parents. He was sentenced to two consecutive life sentences, plus an additional six years for forgery.
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