Susan and Michael MacIvor on their wedding day


Missy and Michael MacIvor wedding photo


Thomas Michael Overton


Summary of Offense:

On August 22, 1991, the bodies of Susan and Michael MacIvor were found in their home in Tavernier Key by concerned neighbors and coworkers. Ms. MacIvor was eight months pregnant. When law enforcement searched their house, they found Mr. MacIvor’s body in the living room. The room appeared as if a struggle had taken place.

Mr. MacIvor was dressed in a T-shirt and his underwear. His head was covered with masking tape so that only part of his nose was exposed. There was a blood spot on the shoulder of the T-shirt. 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. Her body was on the bed on top of the comforter. 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.

A dresser drawer was open in the bedroom that led to the officers to conclude that the articles that were used to secure Ms. MacIvor belonged to the victims. Ms. MacIvor’s eyes were covered with masking tape. Several items were found under the comforter: items that appeared to have come from Ms. MacIvor’s purse as well as her nightshirt and panties. 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. A .22-caliber shell casing was found in the bedroom along with a bullet hole in the bedroom curtain. In addition, an address book with pages torn out was also found. The sliding glass doors in the bedroom were open and a box fan was running. There had been a heavy rain storm the night before, which, combined with the heat, had left a layer of moisture on Ms. MacIvor’s body. In the guest room, the sliding glass doors were also open. A ladder had been propped up against the house near the guest bedroom balcony. The clothesline from the balcony had been cut. A piece of clothesline rope had been found outside of the master bedroom door. Outside the house, the phone wires had been cut with a sharp instrument.

The medical examiner testified to findings from the autopsy. Mr. MacIvor suffered a severe blow to the back of the head. There was bruising around the larynx. The larynx, hyoid bone, and epiglottis had been fractured. There was bruising and an internal contusion which reflected a heavy blow to the back of the head. There were ligature marks on his neck indicating the device was wrapped around his neck several times. Internally, the neck was unstable and dislocated at the fifth cervical vertebrate. There was internal bleeding in his left shoulder, signifying a severe blow. He also had bruising in the abdominal area that could have been caused by a strong kick to the stomach. The cause of death was reported as asphyxiation by ligature strangulation. The medical examiner estimated that Mr. MacIvor was conscious for 10 to 15 seconds after the ligature was placed around his neck, although he limited his opinion by stating that it would have depended upon the amount of pressure that was used.

Ms. MacIvor’s body had several abrasions on her face, genitals and legs in addition to ligature marks around her neck and wrists. The medical examiner stated that it appeared that she had moved against the ligature causing friction. Her face was discolored due to the partial application of the ligature. This caused the blood to enter the head at the normal rate, but it was unable to exit as quickly, in addition to increasing the time that it took to render Ms. MacIvor unconscious. Ms. MacIvor was eight months pregnant. The medical examiner testified that the male child would have been viable if Ms. MacIvor had given birth. The child lived approximately 30 minutes after Ms. MacIvor passed away. Evidence indicated that the child tried to breathe while still in the womb.

During the initial stage of the investigation, tests were run on the stains found on the mattress pads and the sheets, which tested positive for sperm. The swabs of Ms. MacIvor’s body did not reveal any spermatozoa. The medical examiner attributed this contradiction to the moist climate in which Ms. MacIvor’s body was found. This climate provided the environment for the seminal fluid to decompose leaving no sperm. 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.

This DNA evidence was presented at Overtons’ trial in addition to the testimony of two witnesses. The first witness was William Guy Green. Green testified that Overton admitted to him that he had committed a burglary in a wealthy neighborhood in the Florida Keys. Overton related the events that occurred to Green stating that he entered the house and fought with the woman, who had jumped on his back. He also stated that he had fought with another individual in the house. Overton told Green that he to “waste somebody in the Keys.” Overton discussed the safety measures that he would utilize when he committed burglaries, such as cutting the phone wires to the house, wearing gloves, and bringing along equipment such as a gun, knife, gloves and disguises. Overton also told Green that the best time to burglarize a house is during a power outage or a storm.

The second witness was James Zientek. Overton had met Zientek in the Monroe County jail in May 1997. Overton related all of the details of the two murders to Zientek so that Zientek could relate to law enforcement that he had heard the story from another inmate thereby creating reasonable doubt for Overton. The following events are what Overton told Zientek: Overton had met Ms. MacIvor at the Amoco station by the victim’s house where he had worked. He described Ms. MacIvor as being “hot and cold” due to the fact that on some days she was nice and other days she was “bitchy.” Overton had gotten Ms. MacIvor’s address from one of her checks. He had observed the house prior to the night of the murder on several occasions.

On the night of August 21, 1991, Overton went to the MacIvor’s home. He was dressed in all black with a mask and gloves. He cut the phone wires and then leaned a ladder against the balcony. This movement made some noise and subsequently a light came on in the house. Overton waited 20 minutes before entering the house. He climbed up the ladder, and when he reached the balcony, he cut the clothesline, “popped” the sliding glass doors in the guest bedroom and entered the house. He walked through the house and viewed the MacIvors sleeping. Overton continued to walk around the house and, at one point, he heard a noise and he looked to see Mr. MacIvor walking to the kitchen and then opening the refrigerator. According to Overton, Mr. MacIvor must have sensed that something was wrong because he began to look around and Overton panicked.

Overton came at Mr. MacIvor from behind and hit him in the head with a pipe from the house. Mr. MacIvor was not rendered unconscious immediately, so Overton hit him with his fists to knock him out. At this point, Ms. MacIvor ran out of the bedroom, and Overton then chased her back into the bedroom. Overton tied her up with items that he found in the bedroom and tried to talk to Ms. MacIvor telling her that if everyone cooperated no one would get hurt.

Ms. MacIvor told Overton that she knew who he was. Overton became concerned about Mr. MacIvor coming to. He went back to the living room and placed a sock over Mr. MacIvor’s eyes and put masking tape around his entire head. Overton’s rationale for this behavior was that he did not want Mr. MacIvor’s eyes to pop out of his head, and he knew that his nose would bleed.

Overton went back to the bedroom and raped Ms. MacIvor and then strangled her because he didn’t “want to leave any fitnesses.” Overton stated that, at some point, he saw movement in Ms. MacIvor’s stomach and placed his hand on her belly to feel the fetus move. Overton returned to the living room and saw that Mr. MacIvor was “just becoming conscious.” Overton proceeded to kick Mr. MacIvor in the stomach and then strangle him. Overton also told Zientek that he did not know about the bullet hole and that he tore pages out of the address book to make the scene appear as if the assailant wanted to remove their name from the book.

Overton admitted that his intent when he entered the house was to rape Ms. MacIvor. At the trial, the defense rested solely on the notion that the stains on the bedding had been planted by law enforcement officials; specifically, that a detective had collected some of Overton’s sperm from Overton’s girlfriend and then brought the sample to the crime scene in a condom. Nonoxymol-9 had been found in the samples, but it could not be ascertained whether the substance, used both as a spermicide and as a cleaning agent, originally came from a condom or the detergent used to wash the sheets.

Overton was sentenced to death in Monroe County on March 18, 1999.