With the help of a team from Reed Smith, action movie star and former California Gov. Arnold Schwarzenegger has joined other state governors in asking the U.S. Supreme Court to strike down the practice of partisan gerrymandering once and for all.

Schwarzenegger—with Ohio Gov. John Kasich, Maryland Gov. Larry Hogan and former California Gov. Gray Davis—filed an amicus brief to the high court in support of a lawsuit filed by Republican voters in Maryland challenging the constitutionality of the state's congressional districts.

The filing in Benisek v. Lamone comes roughly a week after the Pennsylvania Supreme Court ruled in League of Women Voters of Pennsylvania v. Commonwealth of Pennsylvania that the state's congressional districts violated the state's constitution and ordered lawmakers to redraw the map, a decision that legal experts say was long overdue. That ruling has been appealed to the U.S. Supreme Court as well.

A high-profile advocate for the end of partisan gerrymandering, Schwarzenegger made it a personal priority to terminate the practice in California, which he and Davis said amounts to “politicians choosing their voters instead of voters choosing their politicians.”

In their court papers, the former and current governors argued that the solution to gerrymandering can't be left to state legislators.

“The compulsion to gerrymander, from our perspective, makes the availability of judicial oversight an imperative,” the governors said in their brief. “Of course, the judiciary must act within recognized constitutional bounds and respect our systemic separation of powers. But it likewise has an unflinching duty to enforce our constitutional mandates.”

The brief was written on behalf of the governors by Pittsburgh-based Reed Smith appellate partner Colin Wrabley, Los Angeles-based insurance recovery partner Ben Fliegel, appellate partners Jim Martin and Brian Sutherland, and associates Patrick Yingling and Devin Misour. That team also penned amicus briefs in Gill v. Whitford, the Wisconsin gerrymandering case pending before the U.S. Supreme Court. Schwarzenegger has been outspoken in that case as well.

Last week the Pennsylvania Supreme Court 5-2 in League of Women Voters of Pennsylvania v. Commonwealth that the state's 2011 congressional map “clearly, plainly and palpably violates the constitution of the commonwealth of Pennsylvania.” The ruling, which found that the congressional map was the result of partisan gerrymandering, also barred its use in the upcoming 2018 election cycle.

On Jan. 25, the two lead defendants in the case, state Senate President Pro Tempore Joe Scarnati and Speaker of the Pennsylvania House of Representatives Michael Turzai, filed an appeal to the U.S. Supreme Court asking that the justices stay the decision. But, according to several court watchers, it is unlikely the highest court in the land is going to consider their appeal.

The lawsuit was filed in the Commonwealth Court by the League of Women Voters and a group of Democratic voters against the state, questioning the fairness of the boundaries that make up Pennsylvania's 18th Congressional District. They claimed that the Republican-controlled Legislature manipulates districts in such a way as to minimize the impact of the state's Democratic voting population.