How a bill becomes law

The short answer

How a bill becomes law

A bill becomes Commonwealth law by passing through both Houses of Parliament in the same form and receiving Royal Assent from the Governor-General. The process typically begins when a bill is introduced into either the House of Representatives or the Senate, though most government bills originate in the House. The bill then passes through a first reading, second reading debate, consideration in detail or committee stage, and third reading in its originating house before moving to the other house, where the same stages are repeated. If the second house passes the bill without amendment, it proceeds to Royal Assent. If amendments are made, the bill returns to the originating house for consideration of those amendments. Once both houses have agreed to the same text, the bill is presented to the Governor-General for assent, at which point it becomes an Act of Parliament.

This is a federal system guide. State constitutions, parliaments and local-government laws can allocate comparable functions differently.

The useful question is not only “what is the rule?” but also “who administers it, which document controls it, and when might it change?” That distinction prevents an accurate general explanation from becoming wrong advice in a particular election, chamber or policy setting.

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Origins of a bill

A bill may be introduced by a minister (a government bill) or by a non-minister member or senator (a private member's or private senator's bill). Government bills usually originate from a policy commitment made by the government, a recommendation from a parliamentary committee, a law reform commission report or a court decision that exposes a legislative gap. The sponsoring department or agency prepares drafting instructions for the Office of Parliamentary Counsel, which drafts the bill text and explanatory memorandum.

The explanatory memorandum is an important companion document that explains each clause of the bill in plain language, sets out the policy rationale and includes a statement of compatibility with human rights. It is tabled alongside the bill and assists parliamentarians and the public in understanding what the bill is intended to do. It is not part of the enacted text but courts may refer to it when interpreting ambiguous provisions.

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House of Representatives stages

In the House of Representatives, the bill's passage proceeds through five formal stages. The first reading is a formal announcement of the bill's title and the tabling of the bill text. No debate occurs at this stage. The second reading is the main policy debate, where the minister moves that the bill be read a second time and delivers a speech explaining the bill's purpose and intended operation. The opposition and other members then debate the bill's principles.

After the second reading debate, the bill proceeds to consideration in detail, where members debate the bill clause by clause and may propose amendments. This stage is optional and may be bypassed if no amendments are proposed. The third reading follows, where the bill is voted on in its final form. If carried, the bill is sent to the Senate with a message requesting concurrence.

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Senate stages and the resolution of disagreements

The Senate follows a broadly similar process of readings and debate, but with some procedural differences including the greater role of Senate committees. A bill may be referred to a Senate legislation committee for inquiry before the second reading debate begins. This allows the committee to invite submissions, hold public hearings and prepare a report with recommendations.

If the Senate passes the bill without amendment, it is returned to the House and proceeds to Royal Assent. If the Senate amends the bill, the amendments are sent to the House for consideration. The House may agree to the amendments, disagree and propose alternatives, or insist on its original text. Where the two houses cannot agree, section 57 of the Constitution provides for a double dissolution of both houses followed by a joint sitting if the deadlock persists after the subsequent election. In practice, most disagreements are resolved through negotiation between the houses.

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Royal Assent and commencement

Once both houses have passed the bill in identical form, it is presented to the Governor-General for Royal Assent. Under section 58 of the Constitution, the Governor-General may assent to the bill, withhold assent, or reserve the bill for the King's pleasure. In modern practice, assent is given as a matter of course on the advice of the government.

After assent, the bill becomes an Act of Parliament and is assigned an Act number for the calendar year. The Act is then published on the Federal Register of Legislation. Commencement is governed by the Act's own commencement provision. An Act may commence on Royal Assent, on a date specified in the Act, on a date to be fixed by proclamation, or in stages with different provisions commencing at different times. Acts that do not specify a commencement date commence 28 days after Royal Assent under section 3A of the Acts Interpretation Act 1901.

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What can stop a bill from becoming law

A bill may fail to become law for many reasons. It may be defeated at any vote in either house. The government may withdraw it if it becomes clear it lacks support. The bill may lapse if Parliament is prorogued or dissolved before it has completed all stages. A bill that passes the House but is not debated in the Senate before the election is called lapses and must be reintroduced in the new Parliament unless it is restored under the Senate's restoration procedures.

The Senate has the constitutional power to reject any bill, including budget bills, though it cannot amend bills that impose taxation or appropriate revenue. The Senate's power to block supply was the subject of the 1975 constitutional crisis, which led to the only occasion on which a Governor-General dismissed a Prime Minister. In ordinary circumstances, negotiation between the government and the Senate crossbench resolves most legislative obstacles.

Common questions

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