The Prince George's County State's Attorney's office says sheriff's deputies had to subdue 44-year-old Johnnie Riley at the Tuesday hearing.
Riley's attorney said his client's actions came after a prosecutor said Riley should be held to a higher standard because of his service in Iraq and position as an officer.
Riley's sentencing was rescheduled for Oct. 15.
Riley was convicted in June of assault, using a handgun during a violent crime and misconduct in office.
In September 2012, prosecutors said Riley shot a handcuffed man in the back after the man got out of a police cruiser and began to run away.