Dr. Larry Blum told the jury at the Will County Courthouse he believes Savio's death was a homicide.
Peterson pleaded not guilty to the 2004 murder of his third wife, whose body was found in a bathtub. Originally ruled an accidental drowning, the case was reopened in 2007 after Peterson's fourth wife, Stacy Peterson, disappeared.
Dr. Blum said injuries on Savio's body, "did not occur from a fall" and it is "extremely rare" for a healthy adult to drown in a bathtub. Under cross examination, Dr. Blum said his opinion has not changed even after reviewing reports from three defense experts who concluded Savio's death was an accident.
Blum said the first pathologist was thorough "for the most part" but noted that the pathologist did not chronicle all of Savio's bruises in print in 2004, just pictures.
"The first doctor, Dr. Mitchell, who passed away, he puts a note at the bottom. It's interesting that the state avoided this that says that the injury in the back of Kathy Savio's head, the big cut that the Dr. Blum pointed out, was consistent with the slip and fall in the bath tub," said Peterson attorney Joel Brodsky.
Criminal defense attorney Kathleen Zellner has worked with Dr. Blum in other cases. She was in the Peterson courtroom on Thursday.
"I know him to be an outstanding witness he has prosecutors and defense attorneys," Zellner said.
The 2004 autopsy by late pathologist Dr. Brian Mitchell reported Savio's death may have been caused by a fall. Under cross examination, defense attorney Ralph Meczyk confronted Dr. Blum with Mitchell's findings. The confrontation continued throughout the afternoon with Meczyk's antagonistic style producing many objections from the prosecution. Meczyk's co-counsel defended him.
"He can be a little bombastic, but he certainly knows what he is doing," Joe Lopez said.
Only Dr. Blum testified Thursday thanks to the many objections from both sides. The jury was asked to leave the courtroom several times.
"Jurors do not like objections. They feel you're hiding evidence, that you're not being straightforward," Zellner said.