Keith Thibeault entered a plea of not guilty at the Ionia County Courthouse Wednesday.
Because it took five months to finish the autopsy, he wasn't arrested until Tuesday.
He's being charged for killing his 3-month-old son Everette. When he was taken to the hospital at the end of March, he had serious brain injuries, a rib fracture, and was bleeding from his liver, stomach and left lung.
The charges against Thibeault are murder and child abuse; enough to send him to prison for life without parole.
But he still may be facing more. At the time of Everette's death, his twin brother Keegan was also suffering from a broken leg.
The prosecuting attorney believes Keegan's injury may have also been caused by Thibeault, but he hasn't been able to find enough evidence against him to charge him.
In the meantime, Keegan has been taken from the custody of both his parents.
With a court-appointed attorney, Thibeault is now preparing for his preliminary exam, happening September 19 at 1:00 p.m.
Keegan and Everette's mother, Nicole Thibeault has visitation rights with Keegan, and is filing for divorce.