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.