Joint convention

A joint session or joint convention is, most broadly, when two normally separate decision-making groups meet together, often in a special session or other extraordinary meeting, for a specific purpose.

Most often it refers to when both houses of a bicameral legislature sit together. A joint session typically occurs to receive foreign or domestic diplomats or leaders, or to allow both houses to consider bills together.

Some Constitutions give special power to a joint session, voting by majority of all Members of the Legislature regardless of which House/ chamber they belong to. For example, in Switzerland a joint session of the two houses elects the members of the Federal Council (cabinet). In India, disputes between Houses are resolved by a joint sitting but without an intervening election.

In the Australian federal parliament, a joint sitting can be held, under certain conditions, to overcome a deadlock between the two houses. For a deadlock to be declared, a bill has to be rejected twice by the Senate at an interval of at least three months, after which a double dissolution election can be held. If, following the election, the new Parliament is still unable to pass the bill, it may be considered by a joint sitting of the House of Representatives and the Senate, and must achieve an absolute majority of the total number of members and senators in order to pass. The only example of this occurring was the Joint Sitting of the Australian Parliament of 1974 under the Whitlam Labor government, at which six deadlocked bills were passed.

Because the House has twice as many members as the Senate, the former has an advantage in a joint sitting. However the voting system used for the Senate before 1949, which might be called "Multiple At Large voting", often led to landslide if not wipe-out results in each state, resulting in a winning margin over the whole of Australia of up to 36-0. That would have given the party or grouping enjoying such a large Senate majority an advantage in any joint sitting, had there been one.

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