True. According to the International Boxing Federation (AIBA) rules, referees are required to wear a black bow tie.
The AIBA rules state that referees must wear a black bow tie when officiating a bout. The black bow tie is meant to represent the referee’s neutrality and impartiality. Referees must also wear a white shirt, black trousers, and black shoes. Additionally, they must have a copy of the AIBA rules and regulations on hand.