From the start, Baltimore County prosecutors have argued that John G. Dietz Jr. and his wife, Lillian, were beaten, stabbed and shot point-blank in the stomach with a shotgun in their farmhouse bedroom.
But yesterday in Circuit Court, an expert medical witness for the defense testified that because of "dramatic differences" in body decomposition, the Dietzes must have been killed at different times, or in different places.
The couple, both 63, were found slain in their bedroom Oct. 28, 1990. The prosecution contends that they were murdered by their adopted son, John G. Dietz III, in the early morning hours of Oct. 25, 1990.
Dietz, 28, has been on trial for a week. The prosecution rested yesterday, and Leslie Stein, Dietz's court-appointed lawyer, put on a brief defense that did not include testimony by Dietz himself. Judge John G. Turnbull said the case would likely go to the jury Monday.
Dr. John E. Adams, a forensic pathologist with 30 years' experience, told the jury of seven men and five women yesterday that the elder Dietz's body was drastically more decomposed than his wife's body.
According to Adams, the body of John Dietz Jr., which was found lying on the bedroom floor, showed signs of serious decomposition. There was advanced "skin slippage" and "blistering," Adams said, and the brain had liquefied.
By contrast, Mrs. Dietz's body, which was found lying on one of the twin beds, showed less serious signs of decomposition. Her body had not yet passed through rigor mortis, or hardening of the muscles after death, as her husband's had.
To assume they had been killed at the same time in the same room, Adams testified, would mean the husband's corpse would have had to have been exposed to 20 to 30 degrees more heat.
"The only other conclusion is that they died at different times," Adams said.
James O. Gentry Jr., one of two prosecutors on the case, suggested during cross-examination that Mr. Dietz's body could have been warmer because he was on the floor, next to a baseboard heater. But Adams did not agree.
At the close of yesterday's session, Stein said Adams' testimony undermines the prosecution's theory of the case and hurts its chances of getting the death penalty.
Earlier, at the close of the state's case, the judge threw out charges of burglary and robbery, saying there was not enough evidence to convict.
The dismissal of the two felony charges means the state's only way to obtain a death sentence is to prove that the murders happened at the same time, and that one was the aggravating circumstance of the other.
"It's sinking fast," said Stein, on the state's chances of getting a death sentence.
In other defense testimony, a resident of Chadwick Manor, which is across Interstate 70 from the Dietzes' 18-acre horse farm, said he saw a man put a briefcase into a red Camaro with handicapped license plates and a tow hitch on Oct. 27, a day before the bodies were found.
The description of the car matches that of a red Camaro that was stolen from the Dietz farm and later recovered at Chadwick Manor.
The witness, Mark Brown, 16, a Woodlawn High School student, said the man he saw by the car wore a baseball cap and had the initials "D.J." shaved in the back of his close-cropped hair.
Asked if the defendant was the man he saw that day, Brown said, "He is not."
August Dietz, a first cousin of the slain Mr. Dietz, also testified that about 5:30 p.m. Oct. 25 he saw the Dietzes' red Camaro driving away from the Dietz farm, followed closely by a black four-wheel-drive truck. Both vehicles had their lights out as they passed him, Dietz said.
Stein said August Dietz's testimony is important because earlier testimony from the defendant's girlfriend proved he was at her house watching television at that time.