Thomas Overton Murders 3 In Florida

Thomas Overton was sentenced to death by the State of Florida for three murders

According to court documents Thomas Overton would break into the home of Michael and Missy MacIvor and in the process of robbing it would murder the two homeowners and their unborn child

Thomas Overton would be arrested, convicted and sentenced to death

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DC Number:911193
Birth Date:11/05/1955
Initial Receipt Date:07/13/1999
Current Facility:UNION C.I.
Current Custody:MAXIMUM
Current Release Date:DEATH SENTENCE

Thomas Overton Case

On August 22, 1991, Susan Michelle MacIvor, age 29, and her husband, Michael MacIvor, age 30, were found murdered in their home in Tavernier Key. Susan was eight months pregnant at the time with the couple’s first child.

Susan and Michael were last seen alive at their childbirth class, which ended at approximately 9 p.m. on August 21, 1991.   Concerned co-workers and a neighbor found their bodies the next morning inside the victims’ two-story stilt-house located in a gated community adjacent to a private airstrip.

Once law enforcement officers arrived, a thorough examination of the house was undertaken.   In the living room, where Michael’s body was found, investigators noted that his entire head had been taped with masking tape, with the exception of his nose which was partially exposed.   He was found wearing only a T-shirt and underwear.   There was a blood spot on the shoulder area of the tee-shirt.   When police removed the masking tape, they discovered that a sock had been placed over his eyes, and that there was slight bleeding from the nostril area.   Bruising on the neck area was also visible.   The investigators surmised that a struggle had taken place because personal papers were scattered on the floor near a desk, and the couch and coffee table had been moved.   A small plastic drinking cup was also found beside Michael’s body.

Continuing the search toward the master bedroom, a piece of clothesline rope was found just outside the bedroom doorway.   Susan’s completely naked body was found on top of a white comforter.   Her ankles were tied together with a belt, several layers of masking tape and clothesline rope.   Her wrists were also bound together with a belt.   Two belts secured her bound wrists to her ankles.   Around her neck was a garrote formed by using a necktie and a black sash, which was wrapped around her neck several times.   Her hair was tangled in the knot.   Noticing that a dresser drawer containing belts and neckties had been pulled open, officers believed that the items used to bind and strangle Susan came from inside the home.   Her eyes were covered with masking tape that appeared to have been placed over her eyes in a frantic hurry.   Under the comforter upon which the body rested were several items which appeared to have been emptied from her purse.   Also under the comforter was her night shirt;  the buttons had been torn off with such force that the button shanks had been separated from the buttons themselves.   Near the night shirt were her panties which had been cut along each side in the hip area with a sharp instrument.

Within the master bedroom, the investigators also found a .22 caliber shell casing, and somewhat later a hole in a bedroom curtain was noticed.   Also in that bedroom, the officers found an address book with some pages partially torn out.

The sliding glass door in the bedroom was open and a box fan was operating.   There had been a heavy rain storm the night before and the heat and humidity were quickly rising.   As a result of these conditions, Susan’s body was covered with moisture.   The investigators used a luma light to uncover what presumptively appeared to be seminal stains on Susan’s pubic area, her buttocks, and the inside of her thighs.   The serologist later testified that he collected what appeared to be semen from Susan’s body with swab applicators.   Three presumptive seminal stains also appeared on the fitted sheet.   Within close proximity to one of the seminal stains on the fitted sheet, a stain which appeared to be dried feces was located.   It was also noticed that Susan had fecal matter in her buttocks area.   Ultimately, the officers took the comforter, fitted sheet, and mattress pad into evidence.

The investigation next proceeded to a spare bedroom, which was then being renovated for use as a nursery for the baby.   The sliding glass door in that room was also open.   A ladder was found propped up against the balcony outside the nursery.   Cut clothesline rope was hanging from the balcony ceiling, and outside the home, the phone wires had been recently cut with a sharp instrument.

The medical examiner’s testimony at trial established multiple factors.   As to Michael, the autopsy revealed that he suffered a severe blow to the back of the head.   The external examination of Michael’s neck revealed several bruises particularly around the larynx, along with ligature marks which indicated that the device used to strangle Michael had been wrapped around his neck several times,1 and that pressure was applied from behind.   The internal examination of Michael’s neck confirmed that his larynx, as well as the hyoid bone and epiglottis, had been fractured.   There was also bruising and an internal contusion indicative of a heavy blow to the back of the neck.   The internal examination of the neck area revealed that the neck was unstable and dislocated at the fifth cervical vertebrae.   There was also internal bleeding in the left shoulder, indicative of a severe blow to the area.   Additionally, Michael had significant bruising in his abdominal area causing a contusion fairly deep within the abdomen.   The doctor testified that the injury could have been inflicted by a strong kick to the area.   Based on his observations, the doctor opined that the cause of death was asphyxiation by ligature strangulation (rope).   He added that Michael could have been rendered unconscious ten to fifteen seconds after the ligature was applied, or that it could have taken longer depending on the pressure applied.

With respect to Susan, the external examination of her face revealed that she had received several slight abrasions.   The ligature marks around her neck indicated that she was moving against the ligature, thereby causing friction.   Also, the discoloration in her face indicated that blood was not exiting the head area as fast as it was entering.   According to the medical examiner, this is indicative of an incomplete application of the ligature, which demonstrated that, more likely than not, a longer period of time passed before Susan lost consciousness once the ligature was applied. Her wrists also exhibited ligature marks and her hands were clenched.   Moving down to her lower body, an abrasion to her vulva and several abrasions to her legs indicative of a struggle were found.   The medical examiner concluded, based on the totality of the circumstances, that she had been sexually battered.   When interrogated for an explanation of the presence of feces in the rectal area, the doctor determined that it could have happened either at the time of death or it could have been caused by her fear.

The medical examiner determined that Susan was approximately eight months pregnant at the time and proceeded to examine the fetus. The doctor determined that the baby would have been viable had he been born, and that he lived approximately thirty minutes after his mother died.   The doctor testified that there was evidence that he tried to breath on his own.

Dr. Pope, the serologist, examined the bedding and made cuttings in accordance with the markings he had made at the scene.   One of the stains from the fitted sheet and another stain from the mattress pad tested positive for sperm.   The cuttings were later sent to FDLE for DNA testing.2  Examination of the swabs from Susan’s body failed to reveal the presence of sperm cells.3

The discovery of this death scene produced a large-scale investigation, and comparable media coverage focused on the murders.   Over the years following the murders, law enforcement agencies investigated several potential suspects.   Through this investigatory process, Thomas Overton’s name was brought up during a brain-storming session in May 1992.   The reason he was considered a suspect was because he was a known “cat burglar,” whom police suspected in the murder of 20 year old Rachelle Surrett.4  At the time of the MacIvor murders, Overton worked at the Amoco gas station which was only a couple of minutes away from the MacIvor home.   Janet Kerns, Susan’s friend and fellow teacher, had been with Susan on several occasions when Susan pumped gas at that Amoco station.   No further investigation was undertaken with respect to Overton at that time.

In June of 1993, the cuttings from the bedding were sent to the FDLE lab in Jacksonville where James Pollock, an expert in forensic serology and DNA identification, proceeded to examine the cuttings.   Through a process known as restriction fragment length polymorphism (“RFLP”), Dr. Pollock was able to develop a DNA profile from two of the cuttings (i.e., one cutting from the fitted sheet and another from the mattress pad).   Specifically, the profile was developed by examining the DNA at five different locations, known as loci, within the chromosomes.   Dr. Pollock compared the profile to samples from several potential suspects.   No match was made at that time.

In late 1996, Overton, then under surveillance, was arrested during a burglary in progress.   Once in custody, officers asked him to provide a blood sample, which Overton refused.   Days later, Overton asked correction officers for a razor, and one was provided.   Overton removed the blade from the plastic razor using a wire from a ceiling vent, and made two cuts into his throat.5  The towel that was pressed against his throat to stop the bleeding was turned over to investigators by corrections officers.   Based on preliminary testing conducted on the blood from the towels, police obtained a court order to withdraw the defendant’s blood for testing.

In November of 1996, over five years after the murders, Dr. Pollock was able to compare the profile extracted from the stains in the bedding to a profile developed after extracting DNA from Overton’s blood.   After comparing both profiles at six different loci,6 there was an exact match at each locus.   Dr. Pollock testified that the probability of finding an unrelated individual having the same profile was, conservatively, in excess of one in six billion Caucasians, African Americans and Hispanics.

In 1998, the cuttings from the bedding were submitted to yet another lab, the Bode Technology Group (“Bode”).   Dr. Robert Bever, the director at the Bode lab, testified as to the tests which were conducted on the bedding and the resulting conclusions.   The Bode lab conducted a different DNA test, known as short tandem repeat testing (“STR”), from that performed by the FDLE. Overton’s DNA and that extracted from a stain at the scene matched at all twelve loci.   These results were confirmed by a second analyst and a computer comparison analysis.   Asked to describe the significance of the Bode lab findings, Dr. Bever testified that the likelihood of finding another individual whose DNA profile would match at twelve loci was 1 in 4 trillion Caucasians, 1 in 26 quadrillion African Americans and 1 in 15 trillion Hispanics.

In addition to the presentation of the DNA evidence, the State presented the testimony of two witnesses formerly incarcerated in the same facility with Overton.   The first was William Guy Green, who testified that Overton had admitted to him that Overton had “done a burglary at a real exclusive, wealthy, wealthy area down in the Keys. The guy had his own airplane and a private airway and he could land his plane in his front yard.”   Overton further told Green that when he went into the house, he “started fighting with the lady,” whom he later described as a “fat bitch,” and that “she jumped on his back and he had to waste-waste somebody in the Keys.” Green also testified that Overton stated that he had struggled with another person inside the house.   Green further testified that Overton spoke to him about specific action he would take when he committed burglaries.   Among these precautions were the cutting of phone lines before going into the house to stop victims from calling out or to stop automatic alarm systems;  he would always wear gloves, and he would bring with him a “kit,” consisting in part of a gun, knife, gloves and disguises.   Green also testified that Overton told him that the “best time” to commit a burglary would be during a power outage or severe storm.

The second informant to testify was James Zientek, who met Overton at the Monroe County Jail in May 1997.   Overton, who believed that Zientek was a hardened criminal from New York, sought Zientek’s assistance to carry out a plan that would relieve Overton from the pending charges.   Specifically, Overton planned to give Zientek significant details of the MacIvor murders, and then have Zientek contact authorities and inform them that another inmate by the name of Ace had provided such details.   Using Overton’s logic, this would create reasonable doubt and he would be found not guilty.   Therefore, during the course of several months, according to Zientek, Overton gave Zientek precise details of what occurred in the MacIvor home on the night the couple was murdered.   Overton also showed Zientek pictures related to the crimes, which Overton had obtained to assist his attorneys in preparing his defense.   Specifically, Overton told Zientek that he had met Susan at the Amoco gas station where he worked.   Overton believed that he had a “hot and cold type relationship” with Susan;  some days she was polite to him and others she was “cold and bitchy.”   There came a point when Susan stopped coming to the gas station.   However, according to Zientek, Overton retrieved Susan’s address from either a check or a credit card receipt.   Zientek testified that Overton informed him that he had surveilled the house on several occasions.   On one occasion, Overton had observed Michael doing construction work at the lower level of the house.   Another time, he said he had intended to enter the home, but did not because he realized that the MacIvors had company.

Turning to the events on the night of August 21, 1991, Overton told Zientek that he went to the home carrying a bag, which contained, among other things, a police scanner.   He described his attire as being a Ninja-type suit, consisting of a mask, black military-style fatigues and gloves.   One of the first things Overton completed when he arrived was the cutting of phone wires.   He then positioned a ladder against the balcony that surrounded the house, but in the process of moving the ladder, he made a noise.   A light in the house came on which caused him to wait outside for approximately twenty minutes before ascending the ladder.   Once he reached the balcony, Overton cut some clothesline, “popped” the sliding glass door to the spare bedroom and gained entry into the home.   He walked around the house and saw the MacIvors sleeping in their bedroom.   He proceeded to walk throughout the house, but suddenly he heard a noise and observed Michael walking over to the kitchen and opening the refrigerator.   Overton said he panicked and that his adrenaline started rushing.   Michael started looking around as if he sensed that something was wrong.   Michael walked out of the kitchen and through the area where Overton was then standing.   Overton then approached Michael from behind and “slammed him in the back of the head” with a pipe he had found at the house.   Zientek testified that “the blow to the head with the pipe didn’t immediately knock him out.   There was a struggle and Mr. Overton knocked him out with his fist.”   While Overton was attempting to restrain Michael, Susan ran out of the bedroom screaming.   He chased her back into the bedroom and temporarily restrained her, using articles he found inside the bedroom to bind her.   Overton tried to calm Susan by stating that as long as everyone cooperated no one would get hurt.   However, Susan began to plead with him, inquiring “Why are you doing this to me?”   She told him that she was married, and began to plead with Overton for her husband’s and baby’s life.   Overton also admitted to Zientek that Susan had stated:  “I know who you are.”

At that point, Overton became “concerned about the male just being temporarily knocked out.   He knew that he wasn’t dead.”   He then proceeded to place a sock over Michael’s eyes and covered his face with masking tape.   According to Zientek’s testimony, Overton did not strangle Michael at that point.   Instead, he went back into the master bedroom and raped Susan.   When he had completed his attack, Overton said he strangled her because he “doesn’t leave any witnesses.”   He also stated that either in the process, or after completing the strangulation, Overton noticed motion in her stomach, placed his hand over it, and felt the fetus move.

Overton then returned to the living room area “where the male was apparently just becoming conscious.”   Overton then kicked Michael in the abdominal area and proceeded to strangle him with “some kind of cord.”   Overton “made it very clear that he doesn’t leave witnesses.”   Overton also explained to Zientek that the reason why he placed a sock over Michael’s eyes and tape around his head was because he thought that as he strangled Michael, his eyes would bulge out and he would bleed through his nose.

Appellant continued to show Zientek photographs from the scene.   When Zientek saw a picture of a shell casing and a bullet hole in the curtain, he asked Overton, “Why would they take a picture of that?”   Overton replied that the casing and the bullet hole had nothing to do with the crime.   Overton further stated that he “confuse[d] the crime scene” and ripped pages from the address book in the bedroom because he believed it would lead the police to think that the attacker wanted to remove the assailant’s name from the phone book.   Overton also told Zientek that he took things “nobody would realize were gone.”   The only item which neither law enforcement officers nor the families were able to account for were several pictures that Susan had taken that weekend of her pregnant stomach.   Overton essentially concluded by informing Zientek that he entered the house with the intent to rape Susan.

Zientek also testified that while looking at autopsy photos of one of the victims, he began to vomit.   Overton started to laugh and cautioned Zientek to not get the pictures wet.   Overton also showed Zientek a picture of a small chalkboard in the kitchen where one of the victims had written “renew life insurance.”   Overton laughed and said something to the effect that, “You don’t think they knew what time it was?”

The primary thrust of the defense in the case was centered upon a theme that law enforcement officers, Detective Visco in particular, had planted Overton’s semen in the bedding, which was essential to the prosecution.7  The defense theorized that Detective Visco obtained the defendant’s sperm from Overton’s one-time girlfriend, Lorna Swaybe, transported the sample in a condom, and placed it on the bedding.8

In an attempt to substantiate this fabrication of evidence theory, the defense consulted Dr. Donald Wright, a forensic pathologist.   The doctor suggested that the defense examine the samples from the bedding for Nonoxynol 9, a compound contained in spermicidal condoms.   Relying on this advice, the defense caused the samples to be sent to the lab at the Consumer Products Testing Company in New Jersey.

In the sample labeled as originating from the bottom sheet, the lab director, Mr. Trager, found 53 micrograms of Nonoxynol 9. The state attorney’s office requested a confirmatory test and submitted two new cuttings from the bedding sheet.9  In the first sample, Trager found 50 micrograms of Nonoxynol 9. In the second sample, Trager also found an undetermined amount of Nonoxynol 9.10 Also, 11 micrograms of Nonoxynol 9 were found in a sample from the comforter.11  On cross-examination by the State, Trager testified that there are various forms of Nonoxynol and that the tests he performed did not provide a basis to distinguish whether the Nonoxynol 9 found on the bed sheet was of a spermicidal nature, or whether it was a commercial grade of Nonoxynol 9 commonly used in household detergents.   Although he acknowledged that the perpetrator could have been wearing a condom which might have torn during the course of the struggle with Susan, Dr. Wright continued to opine that the seminal fluid forming the stain on the fitted sheet had been planted through the use of a condom.12

Several factors were elicited during cross-examination.   A spermicidal condom contains 25 to 35 milligrams of Nonoxynol 9. It may be concluded that there are usually 25,000 to 35,000 micrograms of Nonoxynol 9 in one spermicidal condom.   In this case, 53 micrograms were found from the first test sample and 50 micrograms from the second test sample.   Dr. Wright further noted that the initial report he received from Mr. Trager (i.e., the report that led Wright to believe that the seminal fluid had been planted) indicated that the amount found was 53 milligrams (there are 1000 micrograms in 1 milligram), but that a revised report indicated that there had been a typographical mistake and that the actual amount of Nonoxynol 9 present was only 53 micrograms.   Dr. Wright candidly admitted that he did not know the amount of Nonoxynol 9 normally contained in a condom when he initially suggested that the seminal fluid had been planted;  nor did he know that not all condoms contain Nonoxynol 9 or that Nonoxynol 9 was used in detergents.

In response to this defense expert’s testimony presented to support the fabrication theory, the State presented one rebuttal witness, Mr. Richard Oliver, a chemist from the Home Personal Care Industrial Ingredients Division of a national laboratory, the company which is the sole manufacturer in the United States of Nonoxynol 9 as a spermicide.   Oliver testified that Nonoxynol 9 is not only used as a spermicide (i.e., spermicidal Nonoxynol 9), but it is also commonly incorporated as an ingredient in household detergents (i.e., commercial grade Nonoxynol 9).   Mr Oliver testified that as a manufacturer, his company could possibly tell the difference between the two types, given a “significantly large sample.”   He added, however, that after either type of the chemical has been “put out into the environment and say, placed on other objects,” there is no test to distinguish between the two types of Nonoxynol 9. After reviewing the results of the tests performed by Mr. Trager, Oliver concluded that the correct methodology had been used, but based upon sample quantities extracted from the fitted sheet, there was absolutely no way to determine whether the Nonoxynol 9 found was spermicidal (from a condom) or commercial grade (from detergent).   Oliver further opined that it is “most likely” that residue amounts of the commercial grade Nonoxynol 9 remain after the rinse cycle in a standard washing machine.   Ultimately, during closing arguments, the State argued both that the perpetrator might have been wearing a spermicidal condom, or that any amount of Nonoxynol 9 found in the fitted sheet was residue which remained after the sheet had been washed.

At the conclusion of the guilt phase proceedings, the jury found Overton guilty of the first-degree murders of Susan and Michael MacIvor.   The jury also returned guilty verdicts as to the charges of killing an unborn child, burglary, and sexual battery.

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