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Trial begins in mother-daughter murders

The trial of Jason Duane Cooper, the man charged with the April 26, 2006, murders of his mother- and sister-in-law, Robyn and Jenna Liebner, and one count of attempted burglary at the Liebner residence, began March 12 in Department 21 of Vista Superior Court.

Cooper, now 27 years old, showed no emotion as he sat in court and listened to an account of the murders which included evidence that 16-year-old Jenna had been stabbed 56 times and her 53-year-old mother 23 times.

“Look at the defendant’s conduct and actions and I’m confident you will find [Cooper] guilty of attempted residential burglary and first-degree murder with special circumstances of torture and multiple murder,” Deputy District Attorney Kimberlee Lagotta said in her opening statement to the 12-person jury.

Lagotta told the jury that in addition to being responsible for the murders, evidence would demonstrate that Cooper had tried to break into his in-laws’ home one week before the fatal attacks but was thwarted in his attempt when Robyn Liebner heard footsteps in the backyard and called the Sheriff’s Department to report a prowler.

Cooper’s defense attorney, Wilfrid Rumble, a public defender with the County of San Diego’s Multiple Conflicts Office, said in his opening statement that his client was “not guilty by reason of insanity.”

“It is our position that there was not a murder, not torture, in this case,” Rumble said, asking the jury to ultimately render a verdict of manslaughter.

The crime scene

When Deputy District Attorney Lagotta called Sheriff’s Detective Sgt. Jeff Maxin to the witness stand to describe the crime scene, Maxin said the bodies of mother and daughter were found side by side in the foyer of the home.

Upon examination of the blood trail in the home, it was Maxin’s opinion that the women were attacked in the kitchen, living room and foyer. He said from evidence he reviewed, it appeared that Jenna Liebner had been dragged from the living room to the foyer after being attacked.

As graphic as the scene was, there were more revelations to come, Maxin said.

“The severity [of the attack] could not be fully realized until the bodies were moved,” he said, explaining that the depth of the wounds became more exposed at that time. Stab wounds were present on the victims’ necks, chests and faces.

Maxin explained that two different knives were used in the murders, both found at the scene and entered into evidence. One was a serrated style and the other a butcher knife.

Autopsy findings by the San Diego County Medical Examiner showed both mother and daughter sustained defensive wounds to their arms and hands while attempting to fight off their attacker.

Lagotta said the prosecution has trace evidence to present in the case that includes fingerprints/palmprints, blood and DNA. Blood evidence found on a five-foot-tall gun safe located in the Liebners’ garage will also be presented.

Apprehending the suspect

According to earlier sources, Tom Liebner, Cooper’s father-in-law, returned home from work a short time after the murders of his wife and daughter and was said to be searching the property for the suspect when law enforcement and emergency responders arrived.

“Tom returned to find carnage in his home and [Cooper] admitted that he had killed Robyn and Jenna,” said Lagotta. “Out of fear, Tom looked for a way to defend himself and meanwhile, [Cooper] ran.”

The first deputy to arrive at the crime scene, Alan Walbridge, said that as he approached the house in his patrol vehicle he saw Cooper hiding in the bushes along the roadway.

“[Cooper] came out of the bushes with his arms up saying, ‘I did it, I did it, just shoot me,’” Walbridge testified. “Cooper was unarmed… He said a knife was in the bushes.”

Walbridge explained that he cuffed Cooper and placed him in the back of the patrol car, where he became agitated.

“[Cooper] started banging his head on the car; he was covered in blood,” Walbridge said.

Sane or insane?

In his opening statement, defense attorney Rumble contended that Cooper was not guilty by reason of insanity, explaining that his client was a victim of child abuse.

“No one will dispute that [Cooper] was abused horrifically,” Rumble said. “Because of all this abuse, he has post-traumatic stress disorder, which is a mental disease or mental disorder.”

Rumble contended that after Cooper’s traumatic childhood, he became “hyper-vigilant and was always on the lookout for danger so he didn’t relive the abuse.”

“Mr. Cooper has significant features of disassociation,” Rumble explained. “He took himself ‘out of himself’ to survive.”

The family dynamics

Rumble said Cooper, who married the Liebners’ elder daughter, Amber, in October of 2002, had “difficulties in their families” in common with his wife.

The attorney claimed Cooper had poor relationships with his father and mother and that Amber had sought treatment in the past for “a substance abuse problem.”

“They were high school sweethearts and went to Linfield Christian [School] in Temecula together,” Rumble said, adding that Tom and Robyn Liebner were not “excited” about Cooper dating their daughter.

Rumble continued that after graduating from high school, Cooper and Amber moved to the North Hollywood area, away from their families, and in 2003 Cooper enlisted in the military. Rumble said Cooper was “injured in training, given conflicting medications,” and eventually sustained a head injury.

“Eventually he was given an honorable discharge – medical disability – in December of 2004,” Rumble said.

The previous month, the couple had a child; in October of 2005 they moved to Fallbrook, at which time, Rumble said, “They began a reconciliation with the Liebners.”

Over time, Rumble claimed the family dynamics improved and that at the time the murders took place Tom said he wasn’t aware of any hostilities.

Lagotta said she expects the trial to last approximately six weeks.

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