In Petrie's defense, Buh keyed on the word "likely," which was used often in testimony for the state by Alexander and Rockford pediatrician Dr. Raymond Davis. Buh said those physicians offered conflicting testimony about the cause of Ryker's injuries, with Alexander saying they could been caused only by a violent blow to the head, and Davis attributing them to Ryker being shaken.
"These are expert witnesses the state chose to call," Buh said Tuesday. "One witness says one thing, and one says the other."
He drove home his opinion that Ryker wasn't shaken by pointing out his rib had been broken a couple of weeks before Dec. 15, 2015.
"For him to be shaken that violently, I can't see how that fractured rib would not have been reinjured," he said.
Klein responded that whether the boy was shaken didn't matter – he was hurt, by Petrie, and has suffered brain damage likely to be permanent.
“The state does not have to prove that the defendant is particularly good at shaking babies,” she said. “I don’t have to prove that she shook Ryker at all. What the state has to prove is that the defendant knowingly caused great bodily harm to Ryker."
She said all the doctors who testified, two for the prosecution and one in Petrie's defense, agreed Ryker had head trauma and retinal hemorrhages.
“If the defendant knowingly caused those injuries, she is guilty, whether she did it by hitting Ryker, slamming Ryker, or shaking Ryker, or a combination of shaking and impact," she said.