Jurors Call Pathologist’s Testimony a Key to Their Doubt

The failure of a coroner’s pathologist to establish an approximate time of death, and a lack of confidence in the rest of his testimony, played a major role in the jury’s inability to convict former CHP Officer Craig Peyer in the December, 1986, slaying of college student Cara Knott, several jurors said Friday.

Three jurors interviewed by The Times--two of whom voted for acquittal--complained of the poor performance by former San Diego County pathologist Lee Bockhacker, who performed the autopsy on Knott and who testified as an expert witness for the prosecution. The jurors said their discontent with his testimony was unanimous.

Much of the jury’s difficulty with Bockhacker’s testimony stemmed from his confusion over when a procedure used to determine the approximate time of death was performed. The procedure involves taking the temperature of the liver, which experts say retains heat longer than any other organ.

Juror Gregory Cadice said that had a liver temperature been taken at the scene, the jury might have been able to reach a verdict.

Better Data Sought

“(Bockhacker) didn’t know about the liver temperature. He couldn’t establish a time when the girl died. . . . Without this and other information, it was difficult for us to establish a time of death,” Cadice said.

“Had we had better data from the gentleman, we could’ve come to a different conclusion. This information that was sorely lacking could’ve helped us either convict Mr. Peyer or acquit him,” he said.

Juror Carole Riggs said Friday that jurors were also frustrated over Bockhacker’s inability to determine which of the many bruises found on Knott’s body were suffered before or after death. Riggs and others singled out a large bruise over Knott’s right eye that prosecutors said was inflicted by Peyer with his police flashlight. The blow stunned the young woman before Peyer strangled her, prosecutors alleged.

That allegation was crucial to the prosecution’s case because authorities struggled to explain how Peyer was able to strangle Knott with a 48-inch-long rope they said was kept in the trunk of his California Highway Patrol cruiser.

Theory Not Supported

However, several jurors said Bockhacker failed to support the prosecution’s theory that Knott was momentarily stunned before she was strangled because he could not testify when the numerous bruises and other injuries occurred.

“That allegation was not supported by the evidence or by Bockhacker’s testimony. We don’t know how the prosecutor arrived at that,” said juror Victor Dingman.

Peyer is charged with killing Knott on Dec. 27, 1986. A Superior Court judge Thursday declared a mistrial in the case after the jury reported it was hopelessly deadlocked. District Atty. Ed Miller said Peyer will be retried later this year.

“His (Bockhacker’s) testimony left much to be desired,” said Riggs, who voted to acquit Peyer. He didn’t appear to be prepared, she said. “I wasn’t sure if he had the right folder with the right information in his hand when he testified.”

Ill-Prepared Testimony

Dingman, who also voted for acquittal, said the “jury was unanimous in their assessment” that the pathologist was ill-prepared, and he said Deputy Dist. Atty. Joseph Van Orshoven apologized to the jury for Bockhacker’s performance after the trial.

“When the prosecutor has to hang his head in shame and apologize to the public for the ineptitude of the medical examiner, well, that’s got to tell everyone and the coroner’s office something,” Dingman said. “His absolute inability to give any kind of concept as to time of death . . . hindered us greatly.”

In his trial testimony, Bockhacker estimated that Knott died between six and 26 hours before the autopsy, which was performed the day after police say she was killed.

“It was clear that he didn’t do an adequate job. . . . We weren’t satisfied with the information he had, and we kept waiting for the information he didn’t have,” said Cadice, who voted to convict Peyer.

No Plans to Change

Bockhacker and Van Orshoven could not be reached for comment.

But Chief Deputy Coroner Max Murphy said the San Diego County coroner’s office has no plans to change its policy on the use of liver temperatures to determine time of death.

“We don’t have a policy of taking a liver temperature,” he said. “There are those who say it can identify time of death within certain parameters. But others say it is an unreliable tool and can be erroneous also.”

Murphy said the coroner’s office relies on the degree of body rigidity and the presence or absence of blood in the lower portions of the body to approximate time of death.

Knott, 20, was killed near the Mercy Road off-ramp of Interstate 15. Her body was thrown off the nearby Old U.S. 395 bridge 65 feet into a dry creek bed. Police found her body at about 8 a.m. the next day.

Peyer, a 13-year CHP veteran, was arrested Jan. 15, 1987, and charged with murder. His monthlong trial began last Jan. 19 and ended in mistrial Thursday when the jury deadlocked 7-5 for conviction. Jurors deliberated seven days before informing the judge they were unable to reach a verdict.

More than 2,000 Autopsies

Bockhacker testified at the trial that he worked for the Los Angeles County coroner’s office 16 years before coming to San Diego and that he had performed more than 2,000 autopsies. He worked as a San Diego County pathologist for nine months before returning to Los Angeles County, and is now enrolled at USC, where he is taking medical courses.

Bockhacker testified at Peyer’s preliminary hearing in April, 1987, that a liver temperature was not taken on the morning Knott’s body was discovered or when he performed the autopsy at 2:30 p.m. that day.

Pathologists use liver temperature readings as one means of determining approximate time of death when there are no witnesses to a homicide. The liver retains heat longer than any other body organ, losing between one and 1 1/2 degrees of body heat per hour, according to experts. Using a simple incision, coroners insert a special thermometer into the liver and leave it there for three minutes.

Defense attorney Robert Grimes made an issue of the missing liver temperature and argued that if one had been taken at the scene it would have cleared Peyer. Police said Knott, a San Diego State University student, died between 9 and 10 p.m. Grimes argued that other evidence in the case showed she was actually killed after Peyer got off duty at 10:30 p.m.

Routine Procedure

Prosecutors were unable to prove that Peyer had any contact with Knott and instead built their case on circumstantial evidence, much of it based on scientific blood and fiber evidence.

Dr. Ronald Kornblum, a medical examiner with the Los Angeles County coroner’s office, testified for the defense that liver temperatures are routinely taken at the scene of all homicides there when practical.

In a telephone interview Friday, Kornblum said: “A liver temperature helps to establish the approximate time of death. It doesn’t establish the exact time of death, but a liver temperature is helpful in a homicide investigation because the average body under normal circumstances loses heat at between one and 1 1/2 degrees per hour. This information can help you calculate back to establish an approximate time of death.”

However, liver temperatures are also affected by factors such as air temperature, climate, clothing worn by the victim and the victim’s physical makeup, Kornblum added. For those and other reasons, the San Diego County coroner’s office does not advocate taking liver temperatures at the scene, Murphy said.

‘Useless’ Information

Bockhacker created a controversy at Peyer’s murder trial when he suddenly testified last month that a liver temperature of Knott’s body had in fact been taken at 1 p.m., before he began the autopsy.

He testified that the temperature registered 64 degrees, and he used that to estimate that Knott died between six and 26 hours before the autopsy.

However, Kornblum said in the interview that the liver temperature offered by Bockhacker was useless in a homicide investigation.

“It’s crucial that the temperature be taken at the scene. If you take the temperature at some place other than were death occurred, that information is virtually useless. At 64 degrees, my first question would be, ‘What was the temperature (at the scene),’ ” said Kornblum.

“That (64 degrees) could’ve been the temperature of the air, at which case the body had been dead some time. That also could’ve been the temperature inside the morgue. It wouldn’t have necessarily been a temperature reading that would’ve been useful in a homicide investigation,” Kornblum said.

Juror Dingman said the controversy over the liver temperature created doubts about Peyer’s involvement.

“The liver temperature test was the main thing we complained about. Why wasn’t that done at the scene? The time frame between her disappearance and the time she was found would’ve been helpful in establishing a window around her time of death,” Dingman said.