The doorkeepers are badged officers of the United Kingdom Houses of Parliament. The role of doorkeeper dates back to the 1300s, when the Palace of Westminster also served as a court and they served as prison guards. Over time their role changed to that of messengers from Parliament to the king. They wear a uniform of a black long-tailed coat, white bow tie, and a silver-gilt waist badge of office. Underneath each badge hangs a figure of Mercury, the messenger of the gods, symbolic of this early role.