Perfect bicameralism

Equal bicameralism, even known as perfect bicameralism, is a form of bicameral legislature, in which Lower House and Upper House have the same powers and functions. The opposite situation, in which the Chambers have different powers, is known as imperfect bicameralism.

Examples of equal bicameralism are the Congress of the United States of America, the Italian Parliament and the Swiss Federal Assembly.

In equal bicameral legislative process, bill is discussed, amended and approved by one of the two Chambers, then it passes in the other one which may approve it definitively only by not modifying text, otherwise the bill must return again to the first Chamber. At the end, Low House and Upper House must approve bill with an identical text.

In the United States Congress bills are approved in an identical text by both House of Representatives and the Senate. Except for fiscal bills, that according to the American Constitution are approved only by the House of Representatives, in case of disagreement a conference committee is appointed to reach a compromise, even because according to law it is forbidden to amend the mofications of bills more than two times. The committee is usually composed of the senior members of the standing committees that originally considered the legislation in each chamber. The conference committee must negotiate only about points of disagreement and it can not modify parts approved with identical text by the two Chambers. The compromise version must pass both chambers after leaving the conference committee.

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