A Baltimore man who confessed to throwing his 3-year-old son from a bridge has entered the equivalent of an insanity plea to the charges he faces.

Thirty-eight-year-old Stephen Nelson has pleaded not criminally responsible in the death of his son, Turner.

Nelson's trial was scheduled to begin Thursday and has been postponed until February. He will undergo a psychiatric evaluation by court medical staff.

Nelson has told authorities he threw the boy from the Francis Scott Key Bridge in Baltimore on Feb. 3. The boy's body was found in the Patapsco River on July 12.

Nelson is charged with first-degree murder and child abuse. If found guilty and not criminally responsible, he would be committed to a psychiatric hospital rather than prison