Anthony's body was covered in bruises, abrasions and burns - but his cause of death is from blunt force trauma to the head -- where the only visible exterior injuries were a purple bruise on his left ear and abrasions to his nose and cheek.
It was inside Anthony's head where the real and deadly damage was done to his brain.
Anthony's mother Heather Barron and her ex-boyfriend Kareem Leiva are both charged with Anthony's torture and murder, as well as the abuse of two of Anthony's step-siblings. Barron and Leiva have both pleaded not guilty.
On Tuesday, forensic neuropathologist Dr. Cho Lwin of the L.A. County Coroner's Office testified about the severe injuries to Anthony's brain - "multiple blunt force impacts" that ranged in age from one day to three weeks.
Deputy District Attorney Jon Hatami displayed an image of the outer layer of Anthony's brain. Dark red spots showed multiple subdural hematomas - a type of bleeding that occurs between the skull and the surface of the brain.
"This kind of level, you have to have accumulated those kinds of repeated injuries," Lwin said.
Lwin testified that those brain injuries could have been caused by shaking, forcibly slapping or dropping Anthony on his head repeatedly.
Last week, Anthony's step-siblings testified that the night before police and paramedics came to their apartment, Leiva picked up Anthony by the feet and dropped him to the ground head first between 10 and 20 times. Lwin added that Anthony's severe dehydration only made things worse, contributing to blood clots in his brain.
A second coroner, Dr. Juan Carrillo, also took the stand on Tuesday.
"The manner of death, I deem homicide," said Carrillo. "Cause of death would be blunt force head trauma."
On cross-examination, defense attorneys for Leiva and Barron elicited testimony from Carrillo that he did not believe Anthony was malnourished at the time of his death. That testimony flies in the face of firefighters, nurses and doctors who have testified that Anthony was so thin his ribs and hip bones were sticking out.
Also on the stand Tuesday was Roxana Palma, the ex-girlfriend of Carlos Garcia. Garcia is the biological father of one of Heather Barron's children - Angel. Palma testified that she considered herself a stepmother to Angel when she lived with his father between 2015 and 2020.
Barron and Garcia split custody of Angel 50-50 until soon after Angel showed up one day with a large scratch on his leg.
"He would be kind of scared to tell us," Palma testified. "He'd say it was Kareem that did it."
Soon after that, Barron asked Palma and Garcia to take Angel full-time. Palma says Heather told her that "she didn't want to deal with accusations anymore of Angel coming home hurt with bruises and scratches."
Angel went to live with Garcia and Palma full-time in October 2017, just eight months before Anthony died.
Palma also told the court that Garcia told her Angel said Leiva forced the children to fight one another.
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