Constitution, Art. IX is amended by adding after Section 23 the following:
Section 24. Reapportionment. Congressional districts must be reapportioned as follows.
1. Procedure. Beginning in 2021 and every 10 years thereafter, when the Secretary of State has received notification of the number of congressional seats to which the State is entitled and the Federal Decennial Census population count is final, the Legislative Apportionment Commission, established every 10 years pursuant to Article IV, Part Third, Section 1-A, shall review the existing congressional districts. If the districts do not conform to Supreme Judicial Court guidelines, the commission shall reapportion the State into congressional districts.
In making such a reapportionment, the commission shall ensure that each congressional district is formed of compact and contiguous territory and crosses political subdivisions the least number of times necessary to establish districts as equally populated as possible. The commission shall submit its plan to the Clerk of the House of Representatives no later than 120 calendar days after the convening of the Legislature in which apportionment is required. The Legislature shall enact the submitted plan of the commission or a plan of its own in regular or special session by a vote of 2/3 of the members of each House within 30 calendar days after the plan is submitted to the Clerk of the House of Representatives. This action is subject to the Governor's approval, as provided in Article IV, Part Third, Section 2.
2. Court apportionment. If the Legislature fails to make an apportionment within 120 calendar days of the convening of the session in which apportionment is required, the Supreme Judicial Court shall make the apportionment within 60 days following the period in which the Legislature is required to act but fails to do so. In making the apportionment, the Supreme Judicial Court shall take into consideration plans and briefs filed by the public with the court during the first 30 days of the period in which the court is required to apportion.
3. Judicial review. The Supreme Judicial Court has original jurisdiction to hear any challenge to an apportionment law enacted by the Legislature, as registered by any citizen or group of citizens. If a challenge is sustained, the Supreme Judicial Court shall make the apportionment.
Section 25. Apportionment of county commissioner districts. County commissioner districts must be apportioned as follows.
1. Redistricting, generally. Beginning in 2021 and every 10 years thereafter, the apportionment commission established under Article IV, Part Third, Section 1-A shall review the existing county commissioner districts and, as necessary, reapportion those districts in each county to establish as nearly as practicable equally populated districts. The Speaker of the House of Representatives is responsible for calling the commission together to review the county commissioner districts. No action may be taken by the commission without a quorum of 7.
2. Supreme Judicial Court. If the Legislature fails to make an apportionment within the 30 calendar days, the Supreme Judicial Court shall make the apportionment within 60 calendar days following the period in which the Legislature is required to act but fails to do so. In making the apportionment, the Supreme Judicial Court shall consider plans and briefs filed by the public with the court during the first 30 days of the period in which the court is required to apportion.’