BENTON, Ky. — The defense in the Jerry Walker case called just one witness Monday, Maryland-based combustion engineer Dr. Richard Roby. Referencing the prosecution's computer models of the fire, Roby said their theory "doesn't make sense."

The fire in question ripped through the fourth floor of Murray State's Hester Hall back in 1998. Then student Jerry Walker, now 36, was charged but his 2001 trial ended in a hung jury.

Late last year, Walker was re-indicted on charges including arson and manslaughter.

With Walker listening intently, Roby testified the idea the person setting the fire would not have made it to safety without a shield, such as a door, was not true. He also said several windows and doors were likely left open and the prosecution's model, shown to the jury Friday, did not account for that "leakage."

Roby also testified the prosecution's models were made to make one gallon of gas, what Jerry Walker purchased minutes before the fire, work.

Roby said using that amount of gasoline would not have caused a significant or deadly fire. He testified the fire in question would have required at least two and half gallons of gas. One gallon, he said, would have caused minimal damage and he ventured to say, Michael Minger could have survived.

"This fire doesn't kill anybody because it snuffs itself out because of the hallway being sealed. It simply doesn't live long enough in under-ventilated conditions to produce any significant C.O.," he said of a one-gallon gasoline fire.

But because he said he believed more than that gallon of gas was used, it proved deadly. Citing a coroner's report which showed carpet burns on Minger's knees, he said it was likely Minger tried to escape by crawling toward the direction of the stairwell and elevators.

"That's how he knew to escape," he said. "He was being overcome. The smoke was too thick, the heat. He backed up and tried to go back to his room for refuge, made it the doorway of his room at 90 seconds or so and collapsed."

Before the day's end, Commonwealths Attorney Mark Blankenship fired off a round of questions to Roby. He referenced a small fire set at Hester Hall back on Sept. 13, just a few days before the fatal one.

There was not much to the fire, as the jury saw by pictures, just some burned up carpet. But Roby told the jury that was a fire that likely would have resulted from a gallon of gas, something Blankenship said he found hard to believe.

Blankenship also criticized Roby for only studying the prosecution's models and not making his own.

The trial will resume at 9 a.m. Tuesday with Blankenship calling Gregory Gorbett, the fire and explosion analyst who created the models in question.