House Bill 1431, sponsored by Lamberth, seeks to amend Chapter 568 of the Private Acts of 1939, which has undergone several amendments since its inception. The bill specifically deletes Article XII and replaces it with a new Article IX, which is noted to be repealed by a 2025 Amendment. This change reflects an update to the governance structure or regulations pertaining to the City of Portland.

The bill stipulates that it will only take effect if approved by a two-thirds (2/3) vote of the City of Portland's legislative body. The presiding officer of the legislative body is responsible for proclaiming the approval or disapproval of the act and certifying it to the secretary of state. While the act will become effective immediately for the purpose of approval or rejection, it will only take full effect as outlined in Section 2 for all other purposes.