When police searched their house, they found Mr. MacIvor’s body in the living room. His head was covered with masking tape so that only part of his nose was exposed. The body displayed slight bleeding from the nostrils, and there was evidence of bruising on the neck.
Ms. MacIvor’s body was found in the master bedroom. She was completely naked. Her ankles were bound with a belt, masking tape and a piece of clothesline rope. Her wrists were bound with a belt, and there was a belt linking her ankles to her wrists. A garrote made of a necktie and a black sash had been tied around her neck.
Ms. MacIvor’s nightshirt had been ripped off with great force and her panties had been cut by a sharp instrument at each side. A luma light revealed semen stains on Ms. MacIvor’s pubic area, buttocks, and the inside of her thighs. The luma light also exposed semen stains on the sheets. The sheets and the mattress pad were placed into evidence.
It was at this time that law enforcement initially considered Thomas Overton as a possible suspect. He was suspected in another murder, which he was never arrested for. He was a known cat burglar, plus he worked at the Amoco gas station that was located only minutes away from the MacIvor’s residence.
In June 1993, the bedding samples were sent to Florida Department of Law Enforcement (FDLE) for DNA testing. No match was found at that time. In 1996, Overton was arrested during the course of a burglary. While he was in custody, FDLE asked Overton for a blood sample. Overton refused. After his refusal and while still in custody, Overton attempted to commit suicide by cutting his throat.
A blood sample was taken from the towels that had been used during the incident. Preliminary testing of the sample gave law enforcement enough evidence to obtain a court order forcing Overton to relinquish a sample of his blood.
In November 1996, Overton’s DNA was compared to the DNA found on the bedding sample from the MacIvor murders. The comparison produced a match with the probability in excess of one in six billion. In 1998, the samples were submitted to another lab for a different DNA test. Again, the comparison produced a match with the probability of one in four trillion.