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Cadet Trial Hears From M.E.

A blow to the victim's head was the focus Thursday at the murder trial of a former Air Force Academy cadet.

David Graham, 20, is accused of killing Adrianne Jones by smashing her skull and shooting her twice in the head. Prosecutors claim that the cadet and his jealous fiancee, Diane Zamora, killed the teen because Zamora was infuriated by Graham's claim that he'd once had sex with the young girl.

"That's a heavy blow by a large person," Dr. Marc Krouse, deputy chief medical examiner for Tarrant County, testified. He said the 6-foot-1 Graham has the strength it would have taken to strike the heavy blow.

Correspondent Angela Hale of CBS affiliate KTVT-TV reports he also told the jury he does not believe Diane Zamora was strong enough to inflict the blow to Jones' head. Krouse aded that he oes he believe finger imprints left on Jones' neck were inflicted by Zamora.

KTVT's Angela Hale Reports

According to Dr. Krouse, it would have been more difficult for the 5-foot-1 Zamora to have inflicted the head injury.

Dr. Krouse said that either of the two gunshots to Jones' head may have killed her, and added that the blow to her skull appeared to have been inflicted by the butt of a 9-mm handgun that prosecutors say is the murder weapon.

"It would take a larger and more muscular person to inflict that type of injury with that small an object," said Dr. Krouse.

Zamora was convicted of the murder in February and is currently serving a life sentence in prison. If convicted, Graham could receive a life sentence in prison. The state is not seeking the death penalty.

On cross-examination Thursday, Krouse acknowledged that an enraged person may have had the power to have inflicted the head wound, and he acknowledged that he knew nothing about Zamora's strength. At her trial, prosecutors had argued that Zamora struck Jones in the head with a small barbell.

Defense lawyers deny Graham's presence during the murder, and explain he gave a fictional murder confession because he "worshipped" Zamora, his first love. He promised to help her cover up the crime and pledged he would confess with her if she ever got caught.

Jones was murdered Dec. 4, 1995, months before Zamora went off to the Naval Academy and Graham, to the Air Force Academy.

Graham and Zamora were arrested in 1996 after she confessed to a Naval Academy friend. A friend of hers, Kristina Mason, testified earlier that Zamora boasted she got Graham to prove his love for her by killing the other girl. However, during cross-examination, Mason admitted lying to a grand jury.