If you refer to someone as a troublemaker, you mean that they cause unpleasantness, quarrels, or fights, especially by encouraging people to oppose authority. 闹事者
noun [专属名词]捣乱者,闹事者;惹麻烦的人
The fair coordinator has been given powers to expel suspected troublemakers. 那位公正的协调员已被赋予权力,以驱逐涉嫌闹事者。