LANSING — The Michigan Supreme Court heard arguments challenging a proposed November ballot initiative to change who draws congressional and legislative districts every decade.

The justices held a special session on Wednesday and asked many questions during 75 minutes of arguments.

Voters Not Politicians, a group backed by the Michigan Chamber of Commerce, said the constitutional amendment is too broad and proposes a general revision that can only be considered at a constitutional convention. Voters Not Politicians said its proposal addresses a single subject.

The proposal would empower a 13-member independent commission to handle redistricting instead of the legislature, now controlled by Republicans. Critics say the current process results in partisan gerrymandering that hurts democracy.

The state appeals court ordered the initiative on the ballot. Election officials want a ruling by early August.