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Cooper found guilty of first degree murder with torture [update]

The jury hearing the case of the People vs. Jason Cooper rendered their verdict on Monday in Vista Superior Court, finding Cooper guilty of first degree murder with the special circumstance of torture in the killing of his mother-in-law, Robyn Liebner, 53, and sister-in-law Jenna, 16.

Cooper, married to Robyn’s older daughter, Amber, savagely stabbed the two women on April 26, 2006, at their Fallbrook home.

Although Cooper has been found guilty of the crimes, because he pled not guilty by reason of insanity, a second trial to determine whether he was sane or not at the time of the murders has been ordered to start Thursday, April 2.

Cooper was also charged with an attempted burglary of the Liebner residence, which occurred a week prior to the murders, but the jury found Cooper not guilty of the charge.


“The number of knife cuts on Jenna’s body give us so much information,” said Prosecutor Kimberlee Lagotta of the San Diego County District Attorney’s Office. “[Cooper] cutting Jenna with little cuts on her face and taking pieces of her shirt was all about power, control and anger.”

Lagotta claimed these actions were “evidence of torture and tormenting, fear and control” because only three of the initial stabs penetrated her undershirt and came in contact with the 16-year-old’s skin.

Evidence showed that Jenna’s right breast had abrasions that were consistent with a serrated knife and that both a long knife and serrated knife were used on her body.

When images of the young woman’s body were projected on a screen in the courtroom, family members began weeping openly.

“Every time Jenna put her hands up was like a ‘time out’ where [Cooper] could have reflected on his decision, and he decided to continue,” explained Lagotta. “Her left hand was so disabled [from knife slices] that it had no ability to function.”

“This was animalistic – something you see in the wild when an animal attacks its prey,” said Lagotta of the way Cooper followed Jenna throughout the home.

While Lagotta said Cooper was quicker in killing Robyn, she emphasized the viciousness of the attack, which resulted in the woman’s spleen being pulled from her body.

“Imagine the force and pain; imagine the twist that pulled out her organ,” said Lagotta. Family members plugged their ears and averted their faces from the screen during the description.

“These stab wounds are disfiguring and defaming,” said Lagotta. “[The blade was run across her breast] so many times. The knife did not enter Robyn’s chest cavities, so what other purpose did they serve other than to degrade?”

Lagotta said Cooper “thought about it and intended to inflict extreme, prolonged pain. This type of pain is reserved for the purpose of revenge, extortion or other sadistic reason.”

“[Cooper] had the time to think he was going to slash individual [times]; it was not an impulse,” said prosecution. “He had to weigh the decision he was making 56 times with Jenna, 27 times with Robyn.”

What was the motive?

Reasons why Cooper committed the crimes have been offered by both the prosecution and defense, but some who had close relationships with the victims had another opinion.

Argument about literature?

Cooper’s defense attorney, Wilfrid Rumble, told the jury what triggered the killings was an argument between his client and Jenna over a piece of medieval literature.

Rumble said Cooper and Jenna were both fond of books on that subject matter.


Lagotta said in her closing statement to the jury that Cooper had broken into the Liebners’ home the week prior to steal a coin collection, but the collection had been sold several months before.

She contended that the sale started heated discussion amongst family members.

Lagotta said she felt Cooper gave a “preview of things to come” by keeping clothes, a knife and a plastic bag in his car after the attempted burglary, indicating what he was “planning to do.”

Changes to the will?

Some insiders say a recent change Tom and Robyn Liebner made to their will, in regard to the amount of inheritance each of their two daughters would receive, is what ignited Cooper’s rage.

According to these sources, the Liebners wished to have their horses cared for in the event they both perished during the horses’ lifetimes.

The change was said to involve more assets being left to Jenna with the understanding that she would make sure the horses were provided for.

It was disclosed in court that on May 24, 2006, a month after he murdered his in-laws, Cooper told his wife “she deserved so much more from her parents.”

The sanity phase

The second trial, which is being heard by the same jury, is likely to cover much of the same ground as the first when it comes to Cooper’s mental state.

The defense will attempt to prove to the jury that Cooper suffers from post-traumatic stress disorder (PTSD), borderline personality disorder and major depressive disorder and possesses some features consistent with dissociative disorders.

Dr. Ansar Haroun, forensic psychiatrist for the San Diego Superior Court, testified that Cooper suffers from an “explosive, impulsive, narcissistic borderline personality disorder” but said he did not believe Cooper suffers from PTSD.

“With PTSD, there are two different types of symptoms, and [Cooper] has none of these,” said Haroun. “Some symptoms aren’t very specific, such as sleeplessness and feeling depressed.”

Haroun also said Cooper is capable of thought and decision, even though the thought “may not be a wise one.”

The defense will most likely recap what they have referred to as Cooper’s “particularly bad” childhood, which was purportedly riddled with loss and abuse.

“The defendant had a bad life with many traumas, but there was no extreme trauma to cause something comparable to PTSD,” Haroun said. “[Cooper] was leading a normal life with no impairment in function. This is not a lifestyle of someone persistently suffering from mental illness.”

Haroun said Cooper’s depression may have been related to his arrest and jail time, and that he thought Cooper had incidents of suspected malingering (untruths) about his alleged disassociated state.

According to the jail psychiatric record, Cooper claimed to “see demons and devils, other active hallucinations and was under considerable stress.”

Cooper’s defense attorney can be expected to reiterate the fact that his client was placed on suicide watch at one point while in custody and review his history of self-mutilation.

During previous testimony, the prosecution contended Cooper was “fine” before seeing the court psychiatrist, relating that he was “joking with other prisoners before going to the sessions.”

If Cooper is deemed to have been sane at the time of the murders, based on the charges of which he has been found guilty, he stands to serve a life sentence without the possibility of parole.

If deemed insane, Cooper will be hospitalized in an appropriate treatment facility.

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