On Tuesday, PBSO and police in Virginia arrested Sheila Keen Warren in the May 1990 shooting death of Marlene Warren.
PBSO said a person dressed as a clown carrying a flower arrangement and two balloons killed Marlene Warren.
Sheila Keen Warren later married Michael Warren, the victim's husband, in 2002. The couple have been living in Virginia.
The homicide investigation was reopened in 2014.
Detectives said advances in DNA technology, combined with evidence gathered decades ago, show Sheila Keen Warren, now 54, was the killer.
At the time of the shooting, she was an employee of Marlene Warren’s husband, Michael, at his used car lot. Since 2002, she has been his wife.
She was arrested Tuesday at the home she shared with him in Abingdon, Virginia, and was jailed without bail to await transfer to Florida on first-degree murder charges.
Michael Warren, 65, has not been charged, but detectives refused to rule him out as a suspect and said he was interviewed again Wednesday.
Palm Beach County authorities said Thursday the new examination of DNA collected in 1990 gave them what they needed to arrest Sheila Warren, who had been the primary suspect all along. Without it, there might not have been enough evidence to convince a jury, they said.
“You basically get one shot and if you roll the dice and take that chance and she is found not guilty, you never get that chance again,” said sheriff’s Detective Paige McCann. “Sometimes patience is the best.”
She and Sheriff Ric Bradshaw would not give any details on the genetic material or where it was found.
Sheila Warren’s Virginia attorney, Wayne Austin, said: “She looks forward to having her day in court.” Her husband did not return a call to his home.
Witnesses had told investigators in 1990 that Sheila Warren and Michael Warren were having an affair, though both denied it.
Over the years, detectives say, costume shop employees identified Sheila Warren as the woman who had bought a clown costume a few days earlier.
And one of the two balloons — a silver one that read, “You’re the Greatest” — was sold at only one store, a Publix supermarket near her home. Employees told detectives a woman who looked like Warren had bought the balloons an hour before the shooting.
The South West Virginia Regional Jail Authority said Thursday morning that Sheila Keen Warren is still in custody at a facility in Abingdon, Va. She will be sent back to Florida to face first-degree murder charges.
Portions of this article courtesy of the Associated Press