WFPD detectives say the child's mother was also considered a suspect at first, but say information gathered during their investigation led them to arrest Brent Benefield, the child's father.
He's on trial in the 30th District Court for injury to a child causing death and assault causing bodily injury to a family member for alleged continuous violence against his wife.
Benefield pleaded not guilty to those charges.
He was arrested two months after he reported his infant child was unresponsive in his home in the 4300 block of McNiel in February 2012.
Detective Todd Henderson with WFPD's Crimes Against Children Unit testified he spoke to doctors and medical staff at Cook Children's Hospital, where the infant was transferred for treatment, as well as both parents.
He says officers narrowed down a timeline as to when they believe the victim's injuries occurred and they were able to eliminate the child's mother as a suspect because Benefield was the victim's caregiver at that time they think those injuries occurred.
Also during testimony today, Cook Children's staff testified they found multiple bleeds in the infant's brain.
They say he also had healing fractures on three ribs and those fractures had callous formations, so they estimated those partial breaks to be about two to three weeks old from when they saw the infant on February 8, 2012.
They say the four-month-old also had fractures near both shoulders, there was evidence of a ligament injury to his spine, and he had retinal hemorrhages in both eyes.
The final determination in the infant's death is that he died of non-accidental trauma.
Testimony is expected to continue Monday morning.
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