Continuity of Congress

The Constitution lets governors fill Senate vacancies by appointment in most states, but House seats can be filled only by election, which takes months. After the September 11 attacks, in which a fourth hijacked plane may have been headed for the Capitol, Congress and outside commissions studied what would happen if a large number of members were killed. During the Cold War Congress had a secret relocation bunker beneath the Greenbrier resort in West Virginia, maintained from 1958 until a newspaper revealed it in 1992.

In 2005 the House adopted a rule allowing a provisional quorum, based on the number of members able to attend, if a catastrophe left too many members dead or missing to reach the normal majority. A 2005 law requires expedited special elections within 49 days when more than 100 House seats are vacant. The Senate relies on governors' appointments, and each chamber has plans to meet away from Washington, which the Constitution allows if both agree.

A bipartisan Continuity of Government Commission recommended in 2003 a constitutional amendment allowing temporary appointments to fill mass House vacancies, but the House has rejected that approach, arguing that the House should be composed only of elected members. Critics say a provisional quorum could let a handful of surviving members pass laws for the nation and that incapacitated members, who are not vacancies, remain an unsolved problem. The COVID-19 pandemic led the House to allow proxy voting from 2020 to 2023, an arrangement Republicans ended and challenged as unconstitutional.