Citizens Protecting Michigan’s Constitution, the group opposing the redistricting proposal, has asked the Supreme Court to throw out the ballot measure, arguing that it would too broadly change the state constitution. Such broad changes can only be enacted through a state constitutional convention, not through a ballot measure, the group argues.

Schuette’s court brief, filed late Friday, joins Citizens’ cause, though it offers an additional legal argument.

“This issue, which has the potential to fundamentally change the structure of our government, is an issue of great public importance and warrants this Court’s review,” the Attorney General’s Office wrote.

A state board approved the proposal for the November general election ballot last week, after a Michigan appeals court rejected a challenge to the redistricting measure in early June. Opponents are asking the state’s high court to reverse the appeals ruling. The Supreme Court has not yet decided whether to hear the issue.

The case is rich with political intrigue, with Democrats in Michigan generally backing redistricting reform and Republicans (who currently control the state House, Senate and governor’s office) generally opposing the measure. Schuette, the attorney general, is also the frontrunner in the Republican Party primary race for governor. His brief was filed in a court in which Republican-backed justices form a majority.

Katie Fahey, executive director of Voters Not Politicians, told Bridge by email Tuesday that her group’s legal team is still reviewing the brief but believes “the ‘fourth branch of government’ claim made by the Attorney General is without merit.”

“Our proposal operates in the same way” as a commission outlined in the 1963 state Constitution which is allowed to redistrict without the Legislature or Governor’s approval and with limited oversight by the Court, Fahey wrote. “Clearly, the Voters Not Politicians proposal is consistent with what the voters approved in 1963, and does not create a fourth branch of government.”

Schuette’s filing argues that the commission outlined in the 1963 state Constitution was invalidated in 1982 “under federal equal-protection case law” putting redistricting power went back into the hands of legislators.

“There’s some validity” to the point that the last time the redistricting system was changed it was done by constitutional convention, said Justin Long, a law professor at Wayne State University. “But that doesn’t clearly answer the question of whether it needs to be handled through a convention now, or if that was a (prudent) l choice that people made in the early ‘60s.”

Long also said there are plenty of institutions within state governments — including the Attorney General’s office — that take on the powers of several branches of government.

“The rhetoric around the three branches of government are based off of our understanding of federal government,” he said. “But state governments just don’t work that way.”

Dave Doyle, spokesman for Citizens Protecting Michigan’s Constitution, the group that challenged the ballot proposal, said the attorney general made “very good arguments” and that he thinks “the court will come to the right decision.”

The Attorney General’s office did not immediately return Bridge’s request for comment Tuesday.

Voters Not Politicians’ proposal would create a 13-member commission responsible for drawing voting district lines. Right now, legislators hold the pen, with the party in power controlling the process. The nonpartisan Citizens Research Council of Michigan released a report Tuesday morning indicating the state’s voting districts have been drawn in a way that would constitute partisan “gerrymandering” based on several different statistical testing methods.

The Supreme Court has until September 7 to issue a ruling, but has several options for how to proceed. Fahey told reporters last week she expects to hear from the court by mid-to-late July.

Schuette and three other Republicans running for governor — Lt. Gov. Brian Calley, Sen. Patrick Colbeck and obstetrician Jim Hines — have said they would not vote for the proposal if it remains on the ballot come November. They join other Republican leaders such as Senate Majority Leader Arlan Meekhof and House Speaker Tom Leonard in opposing the initiative.

All three Democratic candidates for Governor — former Senate Minority Leader Gretchen Whitmer, former Detroit Health Director Abdul El-Sayed and businessman Shri Thanedar — have voiced support for it.

Voters Not Politicians spokespeople have consistently said the group is nonpartisan and is supported by voters across the political spectrum.