A bill is proposed legislation under consideration by a legislature. A bill does not become law until it is passed by the legislature and, in most cases, approved by the executive. Once a bill has been enacted into law, it is called an act of the legislature, or a statute.
The term bill is primarily used in Anglophone nations. In the United Kingdom, the parts of a bill are known as clauses, until it has become an act of parliament, from which time the parts of the law are known as sections.
In Francophone nations a proposed law may be known as a projet de loi or proposition de loi.
The preparation of a bill may involve the production of a draft bill prior to the introduction of the bill into the legislature. In the United Kingdom, draft bills are frequently considered to be confidential.
In the British/Westminster system, where the executive is drawn from the legislature and usually holds a majority in the lower house, most bills are introduced by the executive (government bill). In principle, the legislature meets to consider the demands of the executive, as set out in the Queen's Speech or Speech from the Throne.
While mechanisms exist to allow other members of the legislature to introduce bills, these are subject to strict timetables and usually fail unless a consensus is reached. In the US system, where the executive is formally separated from the legislature, all bills must originate from the legislature. Bills can be introduced using the following procedures:
Bills are generally considered through a number of readings. This refers to the historic practice of the clerical officers of the legislature reading the contents of a bill to the legislature. While the bill is no longer read, the motions on the bill still refer to this practice.
In the British/Westminster system, a bill is read the first time when it is introduced. This is accompanied by an order that the bill be printed and considered again. At the second reading the general merits of the bill are considered – it is out of order to criticise a bill at this stage for technical defects in drafting. After the second reading the bill is referred to a committee, which considers the bill line by line proposing amendments. The committee reports to the legislature, at which stage further amendments are proposed. Finally a third reading debate at which the bill as amended is considered in its entirety. In a bicameral legislature the process is repeated in the other house, before the Bill is submitted to the executive for approval.
Where a piece of primary legislation is termed an act, the process of a bill becoming law may be termed enactment. Once a bill is passed by the legislature, it may automatically become law, or it may need further approval, in which case enactment may be effected by the approver's signature or proclamation.
Bills passed by the legislature usually require the approval of the executive such as the monarch, president, or governor to become law. Exceptions are the Irish Free State from the abolition of the Governor-General in December 1936 to the creation of the office of President in December 1937, and Israel from its formation until today, during which period bills approved by the Oireachtas and Knesset respectively became/become law immediately (Though, in Israel's case, the laws are ceremonially signed after their passage by the President).
In parliamentary systems, approval is normally a formality, since the head of state is directed by an executive controlled by the legislature. In constitutional monarchies, this approval is called royal assent. In rare cases approval may be refused or "reserved" by the head of state's use of a reserve power. The legislature may have significantly less power to introduce bills on such issues and may require the approval beforehand. In Commonwealth realms the royal prerogative informs this. In the United Kingdom, for example, cases include payments to the royal family, succession to the throne, and the monarch's exercise of prerogative powers.
In presidential systems, the need to receive approval can be used as a political tool by the executive, and its refusal is known as a veto. The legislature may be able to override the veto by means of a supermajority vote.
A bill may come into force as soon as it becomes law, or it may specify a later date to come into force, or it may specify by whom and how it may be brought into force; for example, by ministerial order. Different parts of an act may come into force at different times.
Legislatures give bills numbers as they progress.
In the United States, all bills originating in the House of Representatives begin with "H.R." and all bills originating from the Senate begin with an "S.". Every two years, at the start of odd-numbered years, the United States Congress recommences numbering from 1, though for bills the House has an order reserving the first 20 bill numbers and the Senate has similar measures for the first 10 bills. Joint resolutions also have the same effect as bills, and are titled as "H. J. Res." or "S. J. Res." depending on whether they originated in the House or Senate, respectively. This means that two different bills can have the same number. Each two-year span is called a congress, tracking the terms of Representatives elected in the nationwide biennial House of Representatives elections, and each congress is divided into year-long periods called sessions.
In the United Kingdom, for example, the Coroners and Justice Act in 2009 started as Bill 9 in the House of Commons. Then it became Bill 72 on consideration by the Committee, after that it became House of Lords Bill 33. Then it became House of Lords Bill 77, returned to the House of Commons as Bill 160 before finally being passed as Act no. 29. Parliament recommences numbering from one at the beginning of each session. This means that two different bills may have the same number. Sessions of parliament usually last a year. They begin with the State Opening of Parliament, and end with Prorogation.
In the Irish Oireachtas, bills are numbered sequentially from the start of each calendar year. Bills originating in the Dáil and Seanad share a common sequence. There are separate sequences for public and private bills, the latter prefixed with "P". Although acts to amend the constitution are outside the annual sequence used for other public acts, bills to amend the constitution are within the annual sequence of public bills.