— Found to own shoes with traces of orange wig fibers matching those found in the LeBaron.
— The DNA source of the human hair taken from the car.
Even though early detective work compiled much of the evidence against Keen Warren, charges were never filed and the case went cold. Not until scientific advances in DNA technology would authorities take Keen Warren into custody near her home in southwest Virginia 27 years after the murder.
Within about two hours of the May 26, 1990, shooting, the sheriff's office got an anonymous tip: "You might want to ask Michael Warren and Sheila Keen a few questions."
The female caller's message would foreshadow the focus of the Marlene Warren murder investigation in the days, weeks and months to come.
Michael Warren denied having any role. Detectives learned he was on his way to Calder Race Course in Miami Gardens with friends at the time his wife was shot at their home in the Aero Club community.
Keen said she was busy working as a "repo lady," for Michael's used-car lot, Bargain Motors, in West Palm Beach.
But detectives continued to look at both as suspects.
They discovered Michael and Sheila had been having an affair. They had clerks from a West Palm Beach costume shop pick Sheila out of a photo lineup as the woman who bought a clown costume two days before the slaying.