Presidential succession (other than the Vice President) is
ordered by laws passed by Congress.
Laws that established or re-sequenced the line of succession
include:
Presidential Succession Act (1792) - Senate president pro
tempore and House speaker next in line
Presidential Succession Act (1886) - Cabinet replaced
legislative successors
Presidential Succession Act (1947) - re-added Speaker/president
pro tempore in reverse order
Postal Reorganization Act (1970) - removed Postmaster
General
Renewal of the Patriot Act (2006) - added Secretary of Homeland
Security
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