When the Senate first convened on March 4, 1789, members assumed that their sessions would be conducted behind closed doors, in accordance with the practice of the earlier Continental congresses and the 1787 Constitutional Convention (search).

This assumption reflected the Senate's anticipated low-profile role as an advisory body to the president and as a council of revision for measures passed by the House of Representatives (search).

From its earliest days, however, the Senate (search) came under pressure to open its proceedings, and in 1794 it agreed to conduct its routine legislative sessions in public, as soon as a gallery could be constructed. That gallery opened in December 1795.

Yet the Senate never intended to open its discussions of so-called "executive business," related to treaties and presidential nominations, and it reserved the right to close regular legislative sessions at any time.

In spite of this practice, however, newspapers in the 19th century regularly published accounts of the Senate's secret executive proceedings. As long as the Senate continued to hold its executive sessions behind closed doors, leaks to newspapers persisted.

Finally, in 1929, the Senate changed its rules and opened executive sessions to the public, except in extraordinary instances. It took this action after Sen. Robert La Follette, Jr., (search) pointed out the obvious, that the sources for these stories had to be the senators themselves. He also observed that, in the past, closed door deliberations had offered no particular protection against the approval of nominees who later proved to be corrupt. On June 18, 1929, the Senate yielded to La Follette's logic and voted to make future secret sessions the exception, rather than the rule.

Since 1929, the Senate has conducted fifty-three closed sessions (two of which occurred on the same day in 1972 and two others on the same day in 1986) on both executive and legislative matters. Most of these sessions were closed for reasons of national security. Declassified transcripts of the proceedings have been routinely published in subsequent issues of the Congressional Record (search).

A List of Secret Sessions Held

May 24, 1933 — Impeachment trial deliberations fpr Judge Harold Louderback

Feb. 10, 1934 — Investigation of air and ocean mail contracts involving William P. McCracken, Jr., et al.

Feb. 13 and 14, 1934 — Contempt proceedings against William P. McCracken, Jr., et al.

April 15 and 16, 1936 — Impeachment trial deliberations for Judge Halsted L. Ritter

June 26, 1942 — Naval policies on building battleships and aircraft carriers

Oct. 7 and 8, 1943 — Report on the war fronts

April 11, 1963 — $196 million Nike-Zeus production program

July 14, 1966 — Security agency oversight

Oct. 2, 1968 — Defense Department appropriations

July 17, 1969 — Defense Department appropriations

Dec. 15, 1969 — Defense Department appropriations

Sept. 10, 1970 — Proposed legislative program for the remainder of the 91st Congress

Dec. 18, 1970 — Legislative program for the balance of the session

June 7, 1971 — United States involvement in Laos

May 2 and 4, 1972 — National Security Study Memorandum #1 (there were two sessions on May 2)

Sept. 25, 1973 — Trident submarine

June 10, 1974 — Amendment #1380 on MARV (Maneuverable Reentry Vehicle)

June 4, 1975 — Defense Department appropriations

Nov. 20, 1975 — Intelligence activities

Dec. 17 and 18, 1975 — Defense Department appropriations and Angola

July 1, 1977 — Neutron Bomb

Feb. 21 and 22, 1978 — Panama Canal Treaty and accusations of corruption by the Panamanian leadership

May 15, 1978 — Proposed airplane sales to Egypt, Israel, and Saudi Arabia

Sept. 21, 1979 — Selective Service registration

Feb. 1, 1980 — Armed forces personnel management

May 4, 1982 — Defense issues; United States/USSR capabilities

Feb. 16, 1983 — Nominations of Richard R. Burt and Richard T. McCormack

April 26, 1983 — Nicaragua

Feb. 1, 1984 — Soviet compliance, arms control

June 12, 1984 — Defense authorization bill

Oct. 7-9, 1986 — Impeachment trial deliberations for Judge Harry Claiborne (there were two sessions on Oct. 7)

March 29, 1988 — INF Treaty (held in old Senate chamber)

March 16 and Oct. 19, 1989 — Impeachment trial deliberations of Judge Alcee Hastings

Nov. 2, 1989 — Impeachment trial deliberations for Judge Walter Nixon

Feb. 25, 1992 — Most favored nation status for China (held in old Senate chamber)

April 24, 1997 — Chemical Weapons Convention

Jan. 25 and 26, 1999 — Discuss procedures for impeachment trial of President Clinton

Feb. 9-12, 1999 — Impeachment trial deliberations for President Clinton

Source: Senate Historical Office and Senate Library.