SPOKANE, Wash. — More than a year after police said a Spokane man killed his infant son, we've learned that he's pleaded guilty to the crime.

34-year-old Erik Sherman is now convicted of homicide by abuse.

The doctor who treated his infant son said in the 23 years of practicing medicine, this was the worst case of child abuse they've ever scene.

According to court documents, doctors said when the infant arrived at Sacred Heart Medical Center, he was unresponsive.

They also noted obvious bruising all over his body. X-rays confirmed he had a right clavicle fracture, a fractured femur and right tibia.

Court documents said three separate neurological exams confirmed a serious brain injury with no brain activity.

The child's mother told investigators how they ended up at the hospital. She said Sherman, the child's father, was alone with him on their back patio feeding him a bottle.

He told her when he started burping the child, he suddenly quit breathing.

The mother said two days before this, Sherman had another incident with the child.

She woke up from a nap and found the father with the child in the bathroom with the door partially closed. Court documents show the infant was crying and bleeding from the mouth. Sherman claimed the child suddenly rocked his head forward and hit his mouth on his shoulder, causing him to bleed.

Court papers show they never went to the hospital for this incident. Not even after the mother says he was not able to feed normally.

Investigators said Sherman denied knowing how the child received any of the bruises, a brain injury or broken clavicle.

A few days later, police arrested the father for the death of his child.

Then, just last month, Sherman made a plea agreement and admitted to killing his son by abusing him.

He could face a maximum of 26 years in prison and three years community custody.

Sherman's sentencing is scheduled for Nov. 15.

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