An appeals court on Monday rejected a challenge to Michigan's emergency manager law, saying Gov. Rick Snyder's remedy for distressed communities doesn't violate the constitutional rights of residents.

Emergency managers have exceptional power to run city halls and school districts, while elected officials typically are pushed aside for 18 months or more while finances are fixed. The most significant use of emergency management occurred in Detroit, where Snyder appointed bankruptcy expert Kevyn Orr in 2013. Orr seved for two years.

Critics who sued argued that the law violated a variety of rights — free speech, voting, even protections against slavery — especially in cities with large black populations.

The law might not be the "perfect remedy" but it's "rationally related" to turning around local governments, the 6th U.S. Circuit Court of Appeals said in a 3-0 decision.

"The emergency manager's powers may be vast, but so are the problems in financially distressed localities, and the elected officials of those localities are most often the ones who ... led the localities into their difficult situations," the court said in upholding a decision by U.S. District Judge George Caram Steeh.