1. The mayor may, with the consent of a majority of all the members elected to the board of aldermen, remove from office, for cause shown, any elective officer of the city, such officer being first given opportunity, together with his witnesses, to be heard before the board of aldermen sitting as a board of impeachment. Any elective officer, including the mayor, may in like manner, for cause shown, be removed from office by a two-thirds vote of all members elected to the board of aldermen, independently of the mayor's approval or recommendation. The mayor may, with the consent of a majority of all the members elected to the board of aldermen, remove from office any appointive officer of the city at will, and any such appointive officer may be so removed by a two-thirds vote of all the members elected to the board of aldermen, independently of the mayor's approval or recommendation. The board of aldermen may pass ordinances regulating the manner of impeachments and removals.
2. Nothing in this section shall be construed to authorize the mayor, with the consent of the majority of all the members elected to the board of aldermen, or the board of aldermen by a two-thirds vote of all its members, to remove or discharge any chief, as that term is defined in section 106.273.