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Topic: Yvonne Mathison
May 20th, 2006 10:02 PM
Ferzy On Thanksgiving evening, November 27, 1992, Sergeant Kenneth Mathison and his wife Yvonne drive their 1988 tan Ford van along Route 131 in Hilo, Hawaii. The rain is pouring down and before he knows it, Kenneth Mathison is awaiting police assistance as he cradles his wife’s dead body in the back of their van. Mathison, a sergeant of 25 years with the Hilo Police Department was allegedly informing his wife, a maternity nursing professional at the Hilo Medical Center, that he was being investigated in his second paternity suit. According to Mathison, when Yvonne heard the news, she jumped from the passenger side of the van. While he was looking for her in the blinding rain, Mathison purportedly ran over his wife. He then carried the body into the van and secured it with yellow rope in the back before attempting to find help.

That night, many witnesses reported having seen a man changing the tire of his van and waving any possible help away angrily while others reported seeing a woman wandering around the side of the dangerous highway. More witnesses reported that Kenneth and his wife were having many violent disputes at their home that usually resulted in Kenneth pursuing an angry Yvonne around the block. The most compelling evidence against Mathison, however, is purely scientific. Detective Paul Ferreira first noticed that the extensive blood stains inside the Mathison van. After hearing Mathison’s original account, he summoned the assistance of famed forensic expert Dr. Henry Lee to analyze what he thought was inconsistent evidence. Blood stains on the paneling and the spare tire in the cargo area reveal low-velocity blood stains meaning that the blood probably dripped from Yvonne’s head onto the floor. The stains found on the roof and steering wheel were contact transfer patterns probably caused by Mathison’s bloody hands. Blood stains on the driver’s side of the van were contact-dripping patterns which indicate that Mathison touched the inside of the van multiple times before and after moving his wife’s body. The final groups of blood stains on the instrument panel of the van were medium-velocity stains which show investigators that Mathison probably struck his wife at least once in the front seat causing the blood to fly from her open head wound. The enormous amounts of blood inside the van lead prosecutor Kurt Spohn to investigate the Mathison case as a murder instead of a misdemeanor traffic violation.

In addition to the copious amount of blood stain evidence, many other forensic clues began to mount against Kenneth Mathison. The forensic laboratory at the FBI analyzed the rope that was used to restrain Yvonne and found many of Yvonne’s hairs on it. The hairs were broken in the middle suggesting that the rope was tied with tremendous force, thus contradicting Mathison’s claim that he merely “restrained” his wife’s dead body. An analysis of the outside of the van revealed no recent damage that would have occurred had Mathison actually hit his wife while she was standing, as he claims to have done. Yvonne’s autopsy report also showed that her wounds were not consistent with being hit by a car while standing. She had tire marks on her chest which indicated that she was lying down when she was run over with the family van. She also died with severe skull fractures and a broken ulna in her arm which Dr. Alvin Omori testified could not have come from an auto accident. A fracture mark in the windshield is consistent with a linear, radial fracture pattern but no blood or hair was found in the fracture indicating that is was not caused by Yvonne’s body hitting the windshield.

With Yvonne’s autopsy report in hand and having seen the vehicle, Dr. Lee reexamined the bloodstain patterns which were perhaps the most convincing evidence of Mathison’s guilt. Even the smallest bloodstains were measured and carefully documented by Dr. Lee as he spent ten hours examining the Mathison van. The diameter and angle of impact was carefully calculated in order to help Dr. Lee determine where the blood stains originated from and then what actually happened that night in the van. Bundle’s of hairs were also analyzed and it was determined that Kenneth Mathison severely beat his wife while she was tied up in the back of the van, inflicting multiple skull fractures causing the brain to swell. Yvonne was alive for fifteen minutes after being attacked before her husband laid her bound body on the road in order to run over her chest with the van.

With the evidence gathered by Hilo police officials and Dr. Lee, Kenneth Mathison was convicted of the second degree murder and kidnapping of his wife, Yvonne Mathison, on November 22, 1995.