Dylan James Kitzmiller, 21, received a formal copy of the charges against him Thursday. He and the baby's mother, 26-year-old Maria Elena Sullivan, each face one count of murder, a first-degree felony, and three counts of child abuse, a second-degree felony.
The child was born September 4 with no known health problems, and on September 17 the child was pronounced dead by medical responders in West Jordan, where the couple lived with a relative.
Prosecutors allege Kitzmiller was abusing the child regularly and that Sullivan knew about the abuse but did nothing to stop it or to get treatment for the injuries.
"Both of them were charged because the girlfriend indicated that there was a level of abuse that was going on, she was aware of this abuse, and she took no steps to stop this or to take the child to safety," Gill said.
On the day of the child's death, Sullivan told police she was on the phone with a friend and speaking about her desire to "get away from Kitzmiller's abuse" of her and her son.
West Jordan police requested warrants to arrest both Kitzmiller and Sullivan. Kitzmiller was taken into custody without incident on October 20. After Kitzmiller's arrest, Sullivan traveled to Georgia, where she was also arrested.