LANSING, Mich. (AP) — Michigan Republicans have sued to block the creation of a redistricting commission, contending people would be unconstitutionally prohibited from serving on the panel.

Voters last fall approved a constitutional amendment to have the commission draw congressional and legislative districts instead of the Legislature starting in 2021 — a bid to curtail partisan gerrymandering.

A lawsuit filed Tuesday challenges provisions that bar commissioners from being a candidate for partisan federal, state or local office in the last six years. Others excluded from serving include state employees, lobbyists and political consultants.

Among the plaintiffs are a Republican state senator and party officials. They say the eligibility standards violate their First Amendment rights.

Voters Not Politicians, which spearheaded the redistricting change, says it’s no surprise politicians “want to undermine the voice of voters.”