Press release
Three years from the date he brutally killed Deborah Denise Allen, and just days before he was set to begin his trial in front of a Henderson County jury, Clyde Jason Tennison entered a plea of “Guilty” to her murder before visiting Judge Joe Clayton last Friday.
In exchange for his plea, the 53-year-old Tennison received a sentence of 45 years in the Texas Department of Criminal Justice – Institutional Division. He will be eligible for parole at one-half that sentence (22.5 years), with credit for the time he has been in the Henderson County Jail. He will be 73 years of age before that time arrives, and “eligibility” for parole does not mean he will be released at that time.
On August 2, 2014, Tennison claimed that he and the victim, who was his girlfriend, had been arguing in the days leading up to her death. He told investigators that on the that day, he had just informed her that he was leaving, and went to take a shower first. According to him, when he got out, he looked in her room and saw her body lying on the bed. He then left the house and traveled to the home of his parents, telling them that Deborah had committed suicide by cutting her own throat. He later told Sheriff’s deputy Cayce Hampton that Allen had used his knife to cut herself.
Tennison and members of his family went back to the residence located in Gun Barrel City and determined that Ms. Allen was deceased before contacting law enforcement.
At some point, Tennison consumed and overdosed on Xanax resulting in him being admitted to ETMC the same morning after Allen’s death. He also tested positive for PCP.
As the investigation progressed, Tennison’s account of the events became less plausible. Investigators located the defendant’s wet clothes in the washing machine, yet they still tested positive for the presence of blood. According to lab results, he also had the victim’s blood under his fingernails, along with a distinct bite mark on the inside of his thigh.
The medical examiner who performed the autopsy on Ms. Allen believed that the wounds to the neck of Ms. Allen were unlikely to be self-inflicted. Physical evidence, and the position of the knife found in Allen’s hand were incompatible with the injuries and blood evidence.
Investigators believed that after bludgeoning and cutting his victim, Tennison attempted to stage the scene to appear as if it had been a suicide.
Several weeks after the murder, Tennison made an unsolicited comment to jailers that, “I never thought I would be capable of something like that. I slit her throat and watched her bleed out on the ground.”
During most of the plea, Tennison was quiet and reserved, however during the victim impact statement given by Ms. Allen’s daughter, he momentarily sobbed, and said that he was sorry.
Henderson County District Attorney Mark Hall and First Assistant Nancy Rumar were set to prosecute the case beginning on Tuesday of this week. Hall said that that the plea agreement was one that will ensure that Tennison will be in prison for a long time to come, and that the family of Ms. Allen were fully on board with the 45-year offer.
“This has been a long, hard road for the family of Deborah Allen, and I am glad that they can finally put this chapter behind them. Although the pain of her death will never go away, the fact that Clyde Tennison finally admitted his guilt in open court will help them deal with her horrible death,” Hall said.
“I want to thank the Henderson County Sheriff’s Office, Texas Ranger Michael Adcock, D.A. investigators, and the other law enforcement agencies and personnel that worked this case and did such a thorough and professional job of sorting out truth from fiction.”