Maine constitution
Article IV-3: legislative power
Section 16

No Act or joint resolution of the Legislature, except such orders or resolutions as pertain solely to facilitating the performance of the business of the Legislature, of either branch, or of any committee or officer thereof, or appropriate money therefore or for the payment of salaries fixed by law, shall take effect until 90 days after the recess of the session of the Legislature in which it was passed, unless in case of emergency, which with the facts constituting the emergency shall be expressed in the preamble of the Act, the Legislature shall, by a vote of 2/3 of all the members elected to each House, otherwise direct. An emergency bill shall include only such measures as are immediately necessary for the preservation of the public peace, health or safety; and shall not include (1) an infringement of the right of home rule for municipalities, (2) a franchise or a license to a corporation or an individual to extend longer than one year, or (3) provision for the sale or purchase or renting for more than 5 years of real estate.