Alabama court records show Harrison has an extensive criminal history, including drug and alcohol charges. He received a 30-day jail sentence in 2009 after pleading guilty to hitting another man in the head with a beer bottle. That same year, authorities dismissed a menacing charge against Harrison after the prosecution's main witness failed to show up for trial.
Noblesville Police Detective Michael Sadler said in a probable cause affidavit that officers found the toddler with two knife-stab wounds to his chest and one stab wound from a nail puller in the forehead. Medics pronounced the boy dead Wednesday afternoon at the family's apartment.
The boy's grandmother, Pamela Harrison, told officers that "Micah stated that someone or something was trying to kill him" and that he hit a closet with a hammer, which she took from him, telling the man no one was there.
After she hid the hammer in a bedroom, she saw her son "moving quickly from the kitchen to the other bedroom where she knew Michael was playing." She found her son atop the boy, who was lying on the floor, and watched him stab Michael with the knife.
"Pamela took the knife from Micah and told Micah that he had just killed his son," Sadler wrote.
The first officer on the scene found Harrison with blood on his hands, the affidavit said.
Indiana Department of Child Services spokeswoman Stephanie McFarland said she could not say if Micah Harrison's two daughters, ages 4 and 5, were in state custody due to confidentiality laws, but she did say the agency was involved.