Kyley Harris had previously pleaded not guilty and was scheduled to go to trial on Jan. 13.
Harris was charged following a domestic incident alleged to have happened on May 9.
He was initially placed on administrative leave with pay, but was later fired from his position.
Premier Stephen McNeil said the termination was necessary because Harris waited four days to tell the government he was charged.
Harris is scheduled to return to provincial court for sentencing on March 19.