The Detroit Branch NAACP is asking federal officials to force the state to place on November's ballot a petition that would repeal Michigan's emergency manager law.
The NAACP, activists and religious leaders also filed an emergency motion with the Michigan Supreme Court on Thursday.
The Detroit Free Press says organizers sent a letter to U.S. Attorney Eric Holder and Detroit U.S. Attorney Barbara McQuade accusing the state's high court of using delay tactics to deny residents the right to vote.
The Stand Up for Democracy coalition submitted over 200,000 valid signatures to put the issue on the ballot. Citizens for Fiscal Responsibility claimed the font size on the petitions was too small.
State canvassers deadlocked and Michigan's Appeals Court allowed the signatures, prompting a Michigan Supreme Court appeal.