Updated 08/28/12 – 7:57 p.m.

CHICAGO (CBS) — Two pathologists testifying for Drew Peterson’s defense team said Kathleen Savio fell in her bathtub, knocked herself unconscious, and drowned — rebutting testimony from prosecution experts that her death was a homicide.

Dr. Jeffery Jentzen testified he vehemently disagrees with pathologists who testified for the prosecution that Savio’s injuries were the result of a murder, and could not have been caused by an accidental slip-and-fall.

Jentzen, hired by Peterson’s defense team, said Savio slipped and fell, and was knocked unconscious, then drowned in the water in her tub.

“My opinion is Kathleen Savio died of drowning and the manner of death is accidental,” said Jentzen, who told jurors he has performed 7,000-8,000 autopsies.

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“The injury patterns that I saw were on the left side and over bony areas. These injuries are classic for people who fall.”

Pamela Bosco, a spokeswoman for the family of Peterson’s missing fourth wife, Stacy, said Jentzen’s findings made no sense, and she claimed Jentzen was just saying what defense attorneys wanted him to say.

“He ignored all the scientific data. What doctor gets up on the stand – without being paid – to ignore scientific data that was presented earlier?” she said. “Slipping and falling, you don’t end up in a fetal position with your toes wedged into the tub, lying forward. That’s not a slip-and-fall, and the jury sees right through all that.”

But defense attorney Joe Lopez said it’s ridiculous to suggest Jentzen would present anything but his true expert opinion about Savio’s death.

“I mean this man has, what, a 60-page résumé, as compared to Dr. Blum, which is one page? Not that the length of a résumé means that much, but are you gonna tell me that this guy is going to throw away a career of that length just to testify on behalf Drew Peterson?” he said.

A second pathologist, Dr. Vincent DiMaio, backed up Jentzen’s finding later Tuesday, telling jurors Savio likely fell due to a number of factors – including a wet bathtub with no rubber mat, and her possible use of bath oils.

Both pathologists also pointed out the lack of defensive wounds on Savio’s body as evidence her death was an accident, not a murder. She had no broken fingernails or bruises on her forearms, which the two doctors said would be likely injuries if she had tried to fight off an attacker.

That fit with testimony from a Savio neighbor who said Monday that Savio wouldn’t have let someone attack her without fighting back.

Savio was found dead in her tub in 2004. An initial autopsy ruled her death an accident, but after Stacy Peterson went missing in 2007, authorities reopened the Savio case, and a new autopsy ruled her death a homicide.

Lopez said the two pathologists’ findings that Savio’s death was an accident provides jurors with clear reasonable doubt that Savio was murdered.

“There’s been reasonable doubt since the beginning of the case. This just adds more to it. Like I told you before, the case is like a piece of Swiss cheese, with a bunch of holes in it. This testimony from the doctor is very powerful, very concise,” he said.

The defense expects to rest its case on Wednesday, after calling Drew Peterson’s 19-year-old son, Thomas, who has said he doesn’t believe his father killed Savio, his mother.

“You know, he was there that weekend. He was with his father all weekend. He lived with his mother his entire life, and he has things that he could add to this story that shows – or helps to show – his father’s innocence,” defense attorney Joel Brodsky said.

Defense attorneys also hope the judge will allow testimony that Stacy Peterson asked a lawyer if she could get more money from Peterson by using what she knew about Savio’s death as leverage.

Prosecutors have presented no physical evidence linking Peterson to Savio’s death, have presented no witnesses who saw Peterson kill Savio or saw him at the crime scene at the time of Savio’s death, and have relied largely on hearsay evidence.

If the defense does wrap up on Wednesday, it’s not clear if the case would go to the jury this week or next week.

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