The panel coupled these legislative powers with exclusive access to the information upon which its highly secretive deliberations were based. The joint committee was also entitled by statute to be kept "fully and currently informed" of all commission activities and vigorously exercised that statutory right, demanding information and attention from the executive branch in a fashion that arguably has no equivalent today.
One major power wielded by the JCAE was the "Legislative Veto." This unique power enabled the JCAE to influence policy decisions while matters were pending. This enabled the JCAE to act as a co-decision maker with the executive branch rather than only providing congressional oversight of actions that had already occurred. The legislative veto power was later found to be unconstitutional by the United States Supreme Court in 1983.
During the 1970s, the committee's role in shaping nuclear policy began to diminish after the Nuclear Regulatory Commission was created to replace the Atomic Energy Commission. Congress soon transferred the bulk of the joint committee's jurisdiction over civilian nuclear power to other standing congressional committees in the House and Senate. The joint committee was finally abolished on August 5, 1977.
Brien McMahon (D-CT), 1946-1952: Senator who was legislative author of the Atomic Energy Act of 1946, chairman of the JCAE whenever Democrats controlled Congress (1946, and 1949-1952), until his death. Chairman of the JCAE during detection of the first Soviet atomic bomb, the debate over the hydrogen bomb, and the discovery of Klaus Fuchs as a spy.
Bourke Hickenlooper (R-IA), 1946-1968: Ranking Senator throughout much of its early history; chairman of the JCAE from 1947-1948. In 1949, he led a campaign accusing AEC chairman David E. Lilienthal of "incredible mismanagement" of the US nuclear complex.
The joint committee had equal representation between both the House and Senate, with 5 majority and 4 minority members from each house. The committee was chaired by a senator from the majority party until the 83rd Congress, when the chairmanship began to alternate between a majority representative and majority senator.