South Plainfield Middlesex County Prosecutor Andrew C. Carey announced today that a retired chief of the South Plainfield Police Department has been placed on probation for four years after admitting that he injured a 58-year-old woman and harassed her 8-year-old grandson during a dispute. John Muller, 73, of South Plainfield was sentenced to the probationary term in New Brunswick on November 9, 2015 by Superior Court Judge Michael A. Toto. The judge also ordered Muller to pay the woman’s medical expenses and said the defendant must undergo alcohol and anger management counseling. The sentence was imposed under the terms of a plea agreement reached with Middlesex County Assistant Prosecutor Russell Curley. Under the agreement, Muller pleaded guilty on August 31, 2015 to a third degree count of aggravated assault for injuring the woman and a petty disorderly persons offense of harassment for his treatment of the child. Muller was charged after an investigation determined he was at the South Plainfield Elks Lodge on August 30, 2013 when he grabbed the child by the back of the neck and threatened him. When the woman confronted Muller, he pushed her. She fell and suffered a fractured left wrist.