Crime Library: Criminal Minds and Methods

The Texas Cadet Murder Case

Diane's Trial

"The truth is incontrovertible; malice may attack it, ignorance my deride it, but in the end, there it is."

--Winston Churchill

Zamora in custody (COURT TV)
Zamora in custody

Diane Zamora's two-week trial began in February 1998 in Fort Worth with Judge Joe Drago III presiding. It received national media attention, providing Court TV with some of its highest ratings ever in their film coverage of the capital murder trial. Some of the interest centered on whether she was the submissive victim or the jealous driving force behind the murder.

Under Texas law, murder is the intentional killing of another human being, while capital murder includes murder with an underlying felony of kidnapping, robbery, aggravated sexual assault, arson, or obstruction. In this case, the prosecutor believed that Adrianne Jones was deceptively lured from her home by David Graham asking her for a bogus date, or she would not have been in the car. Moreover, the couple committed obstruction when Zamora allegedly ordered Graham to stalk Jones out into the field and to shoot her so that she could not tell the authorities.

It was only a matter of time before the couple's obsessive love would disintegrate, locking them into a desperate struggle for survival, each claiming the other responsible for the brutal slaying. In fact, Diane's trial began with blaming David and casting doubt on his alleged sexual liaison with Adrianne. The prosecution tried to show that Graham's confession implied that Zamora had some sort of control over him. However, the defense attorney John Linebarger, during his opening arguments, showed a very different picture of the Graham-Zamora relationship. He argued that they had an intense relationship, whereby "David Graham became her mother, father and her lover." Moreover, it was Zamora that was under Graham's control and not the other way around. Linebarger told the jurors that Zamora helped take care of her younger siblings, valued her relationship with Dave, and had held her virginity in high regard.

The defense tried to make the case that Graham was domineering and controlling. Defense forensic psychologist Michael Lobb testified that theirs was a dominant-submissive relationship; a troubled young woman dominated by a controlling young man. He based this on his examination of Zamora and on their exchange of letters. He cites the following letter, August 9th, 1996, as one of the many letters, evidence of Graham's controlling ways:

Diane please respond to this letter soon. I'm CRAAAAAAAZY ABOUT YOU. You know that? You are all MINE, so don't let anyone else near you. You are supposed to follow my rules, as I follow yours. Here are mine, please send yours:





Love, Your Knight, Sir David.

David, the one in charge, according to the defense, had literally "sacrificed" Adrianne Jones in order to keep Diane under his control. "I think he concocted a plan to cover for himself and to bind Diane closer," Linebarger told the jury. "That plan was to kill Adrianne Jones."

However, the prosecution showed another side of Zamora. Lobb's psychiatric report called Diane "a combination of someone who is psychopathically deviant and paranoid. The (testing) would indicate someone who has different views than the normal person in societyangry, resentful and argumentative would be a fair characterization." Following testimony describing Zamora as emotionally weak and dominated by Graham, the defense rested in her murder trial.

In her closing statement, assistant prosecutor Michelle Hartmann told jurors that Zamora acted as "judge, jury and executioner." But some of the most compelling testimony implicating Diane in the murder came from people in whom Diane had confided.

Given Diane's obsessive thoughts, it is not surprising that only a week later she talked to her best friend in high school, Kristina Mason, about her role in Adrianne's murder. As the first witness called by the prosecution, Kristina told the jury that Diane told her that she ordered David to kill Adrianne to prove his love for her. She neglected to tell the police at the time and lied in previous depositions for fear of what might happen to her.

Under cross-examination by the defense, Mason told the jurors about an incident that she witnessed between the couple six months after the murder, during a weekend camping trip. Following an argument between the two lovers, Diane came to her tent crying, upset and afraid of David, asking to stay in Kristina's tent; meanwhile, David slashed the tent with a 14-15 inch knife. The defense also got Kristina Mason to tell that Diane had also admitted to her that Adrianne's murder "shouldn't have happened." From this testimony, the defense tried to portray David as the controller in the relationship, as a domineering, intimidating, and violent figure.

Friends showed another side of Diane. Jay Guild, no longer a cadet, testified, "Diane said that Adrianne deserved to die because she had taken something of hers that she knew belonged to someone else." Jennifer McKearney, who had been a naval academy roommate, testified, "She said any one that got between her and David would have to die."

The last statement that Prosecutor Mike Parrish made to the jury in his closing argument was: "Lives matter, truth matters, Adrianne Jones matters. The only verdict that you can return with the evidence that you have is guilty of capital murder."

After six hours of deliberations over two days, the jury found Diane Zamora guilty of capital murder. She received a mandatory sentence of life in prison, eligible for parole after 40 years. Diane appeared stoic to many onlookers. But, the case was not over yet. "We're only half done," said lead prosecutor Parrish. "The man who pulled the trigger still needs to be brought to justice."

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