Zebaria Dolan, 28, of Alturas, appeared in Modoc County Superior Court on Tuesday on felony charges of first-degree murder and assault on a child causing death.
Dolan, who was left alone for several hours on Dec. 15 with the daughter of his girlfriend, took the 14-month-old toddler to the Modoc Medical Center, where medical staff determined she was the victim of physical abuse, said Modoc District Attorney Jordan Funk.
The girl was comatose and suffering from massive bleeding on the brain, he said.
An initial charge of felony child abuse was changed to murder after the toddler died in a Reno hospital.
Dolan, who has pleaded not guilty, is scheduled for preliminary hearing May 22.