Section 16. Legislative apportionment.

(a) SENATORIAL AND REPRESENTATIVE DISTRICTS. The legislature at its regular session in the second year following each decennial census, by joint resolution, shall apportion the state in accordance with the constitution of the state and of the United States into not less than thirty nor more than forty consecutively numbered senatorial districts of either contiguous, overlapping or identical territory, and into not less than eighty nor more than one hundred twenty consecutively numbered representative districts of either contiguous, overlapping or identical territory. Should that session adjourn without adopting such joint resolution, the governor by proclamation shall reconvene the legislature within thirty days in special apportionment session which shall not exceed thirty consecutive days, during which no other business shall be transacted, and it shall be the mandatory duty of the legislature to adopt a joint resolution of apportionment.
(b) FAILURE OF LEGISLATURE TO APPORTION; JUDICIAL REAPPORTIONMENT. In the event a special apportionment session of the legislature finally adjourns without adopting a joint resolution of apportionment, the attorney general shall, within five days, petition the supreme court of the state to make such apportionment. No later than the sixtieth day after the filing of such petition, the supreme court shall file with the custodian of state records an order making such apportionment.
(c) JUDICIAL REVIEW OF APPORTIONMENT. Within fifteen days after the passage of the joint resolution of apportionment, the attorney general shall petition the supreme court of the state for a declaratory judgment determining the validity of the apportionment. The supreme court, in accordance with its rules, shall permit adversary interests to present their views and, within thirty days from the filing of the petition, shall enter its judgment.
(d) EFFECT OF JUDGMENT IN APPORTIONMENT; EXTRAORDINARY APPORTIONMENT SESSION. A judgment of the supreme court of the state determining the apportionment to be valid shall be binding upon all the citizens of the state. Should the supreme court determine that the apportionment made by the legislature is invalid, the governor by proclamation shall reconvene the legislature within five days thereafter in extraordinary apportionment session which shall not exceed fifteen days, during which the legislature shall adopt a joint resolution of apportionment conforming to the judgment of the supreme court.
(e) EXTRAORDINARY APPORTIONMENT SESSION; REVIEW OF APPORTIONMENT. Within fifteen days after the adjournment of an extraordinary apportionment session, the attorney general shall file a petition in the supreme court of the state setting forth the apportionment resolution adopted by the legislature, or if none has been adopted reporting that fact to the court. Consideration of the validity of a joint resolution of apportionment shall be had as provided for in cases of such joint resolution adopted at a regular or special apportionment session.
(f) JUDICIAL REAPPORTIONMENT. Should an extraordinary apportionment session fail to adopt a resolution of apportionment or should the supreme court determine that the apportionment made is invalid, the court shall, not later than sixty days after receiving the petition of the attorney general, file with the custodian of state records an order making such apportionment.