Overview
The deputy mayor (also known as vice mayor, assistant mayor, or mayor pro tem) is an elective or appointive office of the second-ranking official that is present in many, but not all, local governments.
Duties and functions
Many elected deputy mayors are members of the local government who are given the title and serve as acting mayor in the mayor's absence. Appointive deputy mayors serve at the pleasure of the mayor and may function as chief operating officers.
There may be within the same municipal government one or more deputy mayors appointed to oversee policy areas together with a popularly-elected vice mayor who serves as the mayor's successor in the event the office is vacated by death, resignation, disability, or impeachment.
In other cities, the deputy mayor presides over the city council, and may not vote except to break ties. Like the deputy mayor in other systems, the popularly elected deputy mayor becomes an Acting Mayor in the original mayor's absence. As previously noted in some cities, this office is elected separately and does not entail the elevation by the council of one of its members to be speaker. In some U.S. cities, the mayor and deputy mayor run together as a citywide ticket similar to how the president and vice president run at the national level. In other cities, particularly those with council–manager governments, the council selects one of its members to be vice mayor or mayor pro tem.
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