SAN JOSE (CBS SF) — The county medical examiner who in 2015 ruled an inmate’s death a
homicide by blunt force trauma testified Monday in the murder trial of the three Santa Clara County correctional deputies charged with beating the man to death.

Jereh Lubrin, 30, Rafael Rodriguez, 28, and Matthew Farris, 28, have pleaded not guilty to murder charges in the death of 31-year-old mentally ill inmate Michael Tyree and the assault under color of authority of another mentally ill inmate in San Jose’s Main Jail on Aug. 26, 2015.

Joseph O’Hara, a Stanford University professor of pathology who has worked as a forensic pathologist at the Santa Clara County medical examiner’s office since 2003, arrived at the Main Jail at 4:30 a.m. on Aug. 27, 2015 to examine Tyree’s body after he was found dead in his cell.

O’Hara ruled out the possibility that Tyree’s death had been a drug overdose, citing the lack of drug paraphernalia in the cell or any foam at the mouth characteristic of opiate overdose, or a suicide, despite that writing was found on the wall of his cell.

“I can never know what’s in someone’s head,” O’Hara said, but added that the writing on the wall merely said something about a band and some religious writings, and that he didn’t know who had written it or when.

“I’m not an expert on writing that’s on the wall at jail cells,” O’Hara said.

O’Hara found Tyree lying face-up on the floor of his cell, head away from the cell door and “completely covered with brown particulate” on the front and back sides of his body.

“I think it was a mixture of feces and vomitus,” O’Hara said and described the process by which Tyree’s body was examined before and after cleaning.

Tyree was found with two cuts on his head and a bruise on his cheek along with several dozen bruises and scrapes over the rest of his body, some of which were not visible until he was cleaned off.

O’Hara said the biohazard material found on Tyree’s body did not seem to have evidentiary value, so he did not package it up and take it in as evidence when investigator Chris Garcia returned to the medical examiner’s office at 6 a.m.

O’Hara testified Monday that when he performed Tyree’s autopsy at 10 a.m. on Aug. 28, 2015, he was not aware of inmates’ reports of hearing Tyree screaming while the defendants were in his cell the night he died.

That autopsy included an x-ray through the black body bag, an external exam, collection of trace evidence and documenting any identifying marks, scars and signs of natural disease or injury before cleaning the body and taking photos of his face and body.

The defendants showed little visible response in court Monday when prosecutor Matt Braker projected those photos of Tyree’s pale, slender body, quizzing O’Hara on the cuts, scrapes and bruises found on Tyree’s face and back.

Most of those visible skin injuries, 34 in all, were red or pink, indicating that they had been made around the time of death, O’Hara said.

But the injuries that most likely killed Tyree were the deep lacerations to his liver and spleen, causing 40 to 50 percent of his blood to fill his abdomen.

On her cross-examination, Judith Odbert, defense attorney for Lubrin, questioned O’Hara’s credentials. O’Hara said he had qualified for the American Pathology Board without taking the exam.

Odbert suggested that Tyree could have given himself some of his scrapes by scratching himself, which O’Hara conceded could be true.

“Regardless of whether he scratched his skin or not, his spleen was almost sliced in half,” O’Hara said.

Odbert is set to continue her cross-examination of O’Hara on Tuesday morning.

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