How a Bill Becomes a Law Explained — Processes of Legislation (JAMB/WAEC Government)

Legislation is the process by which a proposed law, called a bill, moves through a series of formal stages in the legislature before it can become an actual law. 

This topic is a regular feature in JAMB and WAEC Government, usually tested by asking students to list or explain the stages a bill passes through. This lesson walks through the full legislative process step by step, from the introduction of a bill to its final assent.

Quick takeaways

• A bill is a proposed piece of legislation that must pass through several formal stages before becoming law.
• The main stages are: first reading, second reading, committee stage, third reading, passage in the other legislative chamber, and presidential assent.
• The committee stage is where a bill receives its most detailed scrutiny, with amendments often made at this point.
• In a bicameral legislature (like Nigeria’s National Assembly), a bill must pass through both chambers before it can proceed to the head of state for assent.
• If the president or head of state withholds assent, some systems allow the legislature to override this through a further vote — a detail often tested directly.

What is a bill?

A bill is a proposed piece of legislation introduced into the legislature for debate and consideration. Until it completes the full legislative process and receives final assent, a bill is not yet law — it remains only a proposal, however far it has progressed through the stages.

What are the main stages a bill passes through?

In most legislative systems, including Nigeria’s National Assembly, a bill passes through these key stages:

1. First reading — the bill’s title is formally introduced to the legislature; no debate takes place at this stage
2. Second reading — the general principles of the bill are debated, and a vote is taken on whether it should proceed further
3. Committee stage — the bill is examined in detail by a relevant committee, where amendments are proposed and debated
4. Third reading — the final, amended version of the bill is debated and voted on in full
5. Passage to the other chamber — in a bicameral legislature, the bill must then go through the same stages in the second chamber (e.g., from the House of Representatives to the Senate, or vice versa)
6. Presidential assent — once passed by both chambers, the bill is sent to the president (or relevant head of state) to be signed into law

What happens at the committee stage, and why does it matter?

The committee stage is where a bill receives its most detailed scrutiny. A smaller group of legislators, often with relevant expertise, examines the bill clause by clause, hears input from stakeholders, and proposes amendments. This stage is often emphasized in exams because it represents the point where the most substantive changes to a bill typically occur, before it returns to the full legislature for further debate.

What happens if the president withholds assent?

If a president or head of state declines to sign a bill (a power often referred to as a veto), most systems provide the legislature with a way to override this, typically requiring a higher voting threshold, such as a two-thirds majority in each chamber. This checks-and-balances mechanism prevents a single individual from indefinitely blocking legislation that has strong legislative support, and it’s a commonly tested detail distinguishing full presidential veto power from a more limited delaying power.

Common mistakes students make with this topic

• Listing the stages out of order, or omitting the committee stage entirely
• Assuming a bill becomes law immediately after passing both chambers, forgetting that presidential assent is still required
• Confusing “first reading” (formal introduction, no debate) with “second reading” (where actual debate on the bill’s principles begins)
• Forgetting that in a bicameral legislature, a bill must pass through both chambers, not just one

Frequently asked questions

Q: What are the main stages a bill goes through to become a law? The main stages are first reading, second reading, committee stage, third reading, passage in the other legislative chamber (in a bicameral system), and finally presidential assent.

Q: What happens during the committee stage of a bill? During the committee stage, a smaller group of legislators examines the bill in detail, proposing and debating amendments before it returns to the full legislature.

Q: What is presidential assent? Presidential assent is the final stage in the legislative process, where the president or relevant head of state formally signs a passed bill into law.

Q: What happens if a president refuses to sign a bill? If a president withholds assent (a veto), many legislative systems allow the legislature to override this decision with a higher voting threshold, such as a two-thirds majority in each chamber.

Want to see how this fits into Nigeria’s broader constitutional structure? Read our Constitutional Development lesson →

This is one topic from our full JAMB & WAEC Government course — see everything covered →