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Diane Kyne died in her Seminole, Florida home, one August afternoon surrounded by two of the men that had been closest to her.
One killed the nail salon owner. The other witnessed the murder. But both men—her adult son and husband—quickly pointed the finger at the other, leaving investigators baffled about who had really taken her life.
“They both immediately accused each other as being the killer,” Pinellas County Sheriff’s Office homicide detective Jim Beining told “Dateline: Secrets Uncovered” in Thursday’s episode on Oxygen. “It’s a difficult case.”
Kevin Kyne was Diane’s 23-year-old son, who was still living at home and recovering from a recent brain surgery to remove a benign tumor.
Her husband, Bill Kyne, had first met her years earlier at the nail salon she ran with her twin sister.
“She was the most wonderful lady I’ve ever met,” he said.
A romance between the pair quickly blossomed and they got married in 2002, when Kevin was 15 years old.
Kevin was so impressed by his mom’s new husband that he asked to take Bill’s last name and officially become a part of the new family. But just eight years later, on Aug. 15, 2010, the two men would be pitted against each other, with each making a deadly accusation.
That afternoon Kevin placed a frantic call to 911.
“Help me, please,” he said. “He killed my mom.”
Kevin went on to tell the dispatcher that his dad was trying take his life.
“He’s outside my house,” he said. “He’s choking me.”
Just minutes later, Bill placed his own 911 call, offering dispatchers a completely different version of events.
“My son just killed my wife,” he said. “He and my wife were arguing and he was choking her.”
Deputies arrived at the scene to find Diane, 49, dead, laying face up on her bed. Investigators would later determine that she had died from asphyxiation or strangulation.
But just who was the killer?
Kevin told investigators that he had been home lying on the couch and watching a NASCAR race when Bill told him his mother wanted to see him. According to his account, he had gotten up and gone into the bedroom, but was immediately attacked by Bill.
“As soon as I pushed the door open, he grabbed me from the back of the neck and put me in a choke hold,” Kevin told Dateline.
Kevin said he began to shout for his mom to help, but realized she was already dead.
“I saw my mom’s face. Her face was black and blue. It wasn’t even blue, it was just black and it was absolutely horrible,” he said. “That’s a mental picture that’s going to be in the back of my mind for the rest of my life.”
Kevin said he was able to break free from Bill during the attack and run down the street to safety.
Bill provided a completely different account of his wife’s death to investigators. He said that he and Kevin had been watching the race on TV together when Kevin got up and went into his mother’s bedroom.
“I hear her howl out ‘Kevin!’ in a loud voice and probably five, 10, 15 minutes goes by and so I get up to see what’s going on, I push the door open and I see Kevin on top of Diane,” he told “Dateline: Secrets Uncovered.”
Bill said he ran into the room and pulled Kevin off his mom, but he was slammed into an armoire as Kevin ran out of the room.
“I caught him at the kitchen, he was throwing me around like I was a rag doll,” he said. “He shook me off again, took off for the door. He ripped the metal off of the door handle, pulling it off so hard.”
According to Bill, the scuffle continued in the front yard, where Kevin’s shirt and shorts—which were both found later laying in the front yard—came off during the fight.
The Case Against Each Man
To make matters more complicated, investigators had reason to suspect both men.
In Bill’s case, Diane wasn’t the first to die in his family. Shortly before he met Diane, his first wife Krista died in the middle of the night at the same Seminole home he later shared with Diane. Investigators believe Krista tripped, hit her head and fell into the pool, where she drowned.
The death was ruled an accident and Bill collected approximately $250,000 from an insurance policy he had on his wife.
He collected other insurance payouts when his automotive shop burned down and again when a fire broke out at an investment property he owned.
Bill had also taken policies out on Diane—which listed him as he beneficiary—totaling $750,000, according to “Dateline.”
Adding to the suspicion, Bill had flunked certain questions on a lie detector test he had willingly taken centered around what had happened to Diane. Investigators were also troubled by the fact that Bill had never gone back into the home to check on Diane after he said he chased Kevin outside.
Reporter Curtis Krueger told “Dateline: Secrets Uncovered” that one of the first deputies at the scene also noticed that Diane’s body had seemed somewhat cold when he arrived, indicating “that she may have been dead for a while” contrary to Bill’s account.
His DNA was also found on a sample taken from her neck.
But Bill insisted he didn’t kill his wife, had never committed insurance fraud and had an explanation for the DNA.
“We were a very loving couple,” he said. “We slept in the same bed together, yeah, my DNA should be on her.”
Investigators also had reason to suspect Kevin may have killed his mom. To start, Kevin had a history of violence. Law enforcement had been called to the family’s home five years earlier after Kevin had gotten into a heated argument with his aunt.
“The police showed up, he fought with the police, and even was trying to have his dog attack the police during it, so he was arrested for battery on a law enforcement officer and resisting arrest,” William Loughery, a former assistant state attorney, told “Dateline: Secrets Uncovered.”
Bill also told investigators that Kevin was often violent when he acted out and had brandished a knife against his mother just three months before her death—a claim which Kevin denied.
“He was frustrated about something and said ‘You’re going to listen to me,’” Bill recalled. “He had a knife in his hand and scared the heck out of her.”
Bill said during another occasion, Kevin had broken down a door after his mother had tried to lock him out of her bedroom.
The couple had even taken legal action to throw Kevin out of the house, but Diane later let her only son move back in.
By the summer of 2010, however, Bill’s family said the tension between Diane and Kevin had grown, with the pair mostly communicating only through email and Kevin verbally attacking his mother in front of the family.
They gave Kevin a deadline to leave the house, but five weeks before the forced move-out date, Diane was killed.
There was also physical evidence connecting him to the scene. Although he told investigators that he had never made it into the bedroom the day his mother was killed, his broken glasses were found at the bottom of her bed, his sandal was strewn nearby and a few drops of his blood were found on his mother’s leg and her bed cover.
Authorities believed it was enough to arrest Kevin for the crime, but after Kevin passed a lie detector test their confidence appeared to waiver and Kevin was released from jail.
It wasn’t until a grand jury indicted him for the murder that the case against him gained momentum.
A jury would ultimately convict Kevin of second-degree murder and he was sentenced to life in prison, but two years later Kevin was granted a new trial after his attorney had argued that a past 911 call Kevin had placed should have not been allowed into the first trial.
This time, his defense team hit the theory that Bill could have been the killer hard and Kevin was found not guilty and released from prison.
Bill would later face his own legal troubles after he was charged in 2019 with leaving the scene of an accident with injury after authorities said he crashed his motorcycle into a group of cyclists, sending one to the hospital, according to the Tampa Bay Times. He also wrote a memoir recounting the death of his wives—including the death of a third wife named Tonya—in the book “Love That Lasts a Lifetime,” PR Web reports.
Kevin also found himself back behind bars in 2016 after he was arrested for a pool hall brawl, the local paper reports.
In Diane’s case, however, no one else has ever been charged and what happened in that Seminole home remains a mystery.
Watch "Dateline: Secrets Uncovered" on Thursdays at 8/7c on Oxygen.
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