Explained: The process that takes legislative bills from proposal to policy

The Montana Legislature can be a daunting institution to keep tabs on. As the 2025 legislative session gears up, MTFP is producing a series of video and text pieces intended to help our readers track their lawmakers and make sense of the headlines they’ll see in the months to come. Up first — a look at the many hurdles bills must clear to become laws.

Any representative or senator can introduce a bill. Depending on which chamber the lawmaker sits in, the Senate President or Speaker of the House will assign the bill to a committee, a topic-focused group of lawmakers from that chamber.

Committees hold public hearings that give lobbyists and the general public a chance to formally weigh in on the bill. Examples of committees are the House Taxation Committee, which hears most tax policy bills, or the Senate Fish and Games Committee, which hears wildlife management bills. A committee might amend a bill before voting on whether to forward it to the floor of the House or Senate.

Once voted out of committee, it takes two votes for a bill to advance on the floor of the full House or Senate. The first is a preliminary vote that comes following a floor debate (this is called the “Second Reading” on official agendas; the “First Reading” is done without fanfare earlier in the process). The second, final vote is usually held without debate the following day (it is formally called the “Third Reading”).

Bills that pass that final chamber vote are forwarded to the Legislature’s other chamber where the process repeats — the bill must generally pass through a committee before going to that chamber’s floor. That means every bill from the House of Representatives gets a second round of review from the Senate, and Senate Bills get a second round of review from the House of Representatives.

Some bills must pass through more than one committee in one or both legislative chambers. Nontrivial spending bills, for example, are often routed through the House Appropriations and/or Senate Finance and Claims committees in addition to committees that consider their policy merits.

Additionally, in rare cases, bills can be pulled onto a chamber floor for debate and potential passage even after a committee has voted them down. This requires a full floor vote, with the procedure commonly called a “blast motion” for its effect in blasting a bill out of committee.

When the House and Senate pass different versions of the same bill, they have to agree on a final draft. In some cases, one chamber agrees to changes made by the other chamber via a floor vote. In other cases, lawmakers set up a conference committee that meets to hash out the differences, with the compromise version going back to both chambers for approval via floor votes.

Once the House and Senate both approve a bill, it’s sent to the governor for his signature. Bills can become law despite a veto by the governor if two-thirds of legislators vote to overrule it.

There’s of course additional nuance to each of these steps — and lawmakers somewhat regularly invoke arcane procedural exceptions as they jockey over highly contested bills. If you’re trying to follow along, read our reporting at montanafreepress.org or visit the state’s official bill tracker for more detail on the process as it applies to specific bills you may be interested in.

Have questions about how the Legislature considers bills that we didn’t address here? Let us know at [email protected] so we can potentially take a crack at them in future coverage.