SANTA ANA (CBS) — Two Fullerton police officers were ordered Wednesday afternoon to stand trial for the beating death of schizophrenic transient Kelly Thomas.

Two doctors testified Tuesday that the weight of the officers holding down 37-year-old Thomas at the Fullerton Transportation Center on July 5 contributed to his death 5 days later.

Officer Manuel Anthony Ramos is charged with second-degree murder and involuntary manslaughter. Corporal Jay Cicinelli is charged with involuntary manslaughter and excessive force.

The 38-year-old Ramos, a 10-year Fullerton police veteran, is free on $1 million bail, one of the highest ever posted in Orange County.

Cicinelli, 42, is free on $25,000 bail. They are both on unpaid administrative leave.Ramos faces a potential sentence of 15 years to life if convicted of second-degree murder but only four years if convicted of involuntary manslaughter. Cicinelli faces a maximum sentence of four years in prison.

The doctors’ testimony is part of a preliminary hearing that began Monday, to determine if there is enough evidence to order the officers to stand trial. During Tuesday’s proceedings, a 35-minute video of the altercation was shown in the court, during which Thomas’ father, Ron Thomas, left the courtroom.

Video of the beating of Kelly Thomas, who died 5 days later.

Pathologist Dr. Aruna Singhania came to her conclusion after performing the autopsy on Thomas’ body and viewing video of the altercation. Besides the violent beating, Thomas had been stunned and hit with a Taser gun.

“The cause of death…is brain death with acute bronchial pneumonia, which is a pneumonia in the lungs, due to mechanical chest compression with blunt cranial facial injury during physical altercation with law enforcement officer,” Singhania said.

Before Thomas died, he was treated at UCI Medical Center by Dr. Michael Lekawa. Dr. Lekawa, under questioning by Ramos’ defense attorney John Barnett, said he initially thought difficulty with a breathing tube could have contributed to Thomas’ death. But Dr. Lekawa determined compression on his chest was a factor in his death after seeing the video and reading Thomas’ medical reports.

“It was during the time when the police officers were on top of him, and he was lying flat – or he was not lying flat, he was down – the police officers were on him, and I could see, or I could hear his mental state when complaining that he couldn’t breathe, and then his capacity to speak appeared to dissipate and eventually he went unconscious,” Dr. Lekawa testified.

In the video, Thomas is obscured by the bodies of at least 4 police officers who subdued him. He can be heard on the tape, moaning and grunting and saying, “OK, I can’t breathe, dude! OK, dude, I can’t breathe, man!”

Ron Thomas and his attorney told reporters their own investigation determined that broken bones in Kelly Thomas’ face and facial cavity caused bleeding in the lungs, which was caused by repeated beating.

Ramos and Cicinelli are due back in court for arraignment May 22.

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