Jonathan Dwyer pleaded not guilty to charges that he assaulted his wife during two arguments in July at their Phoenix apartment.

Dwyer appeared at an arraignment hearing Monday in Maricopa County Superior Court. He is charged with felony aggravated assault and eight misdemeanors, including assault.

Investigators say Dwyer broke his wife's nose with a head-butt during a July 21 argument and engaged in a dispute the following day in which he punched his wife and threw a shoe at his 17-month-old son, who wasn't injured.

He has denied that he committed assault.