The cities supporting the brief include: Baltimore, Boise, Boston, Chicago, Denver, Kansas City, Los Angeles, Milwaukee, Minneapolis, New York City, Philadelphia, Seattle, St. Louis, Tampa and Washington, D.C.
Outgoing Salt Lake City Mayor Ralph Becker, president of the National League of Cities, was among many mayors who issued statements in support of the brief.
"We support President Barack Obama's executive actions on immigration. It's time for our country's humanity to proceed with a solid plan that allows for families to integrate and help thrive in their local community," Becker said.
"We deeply value the positive contribution of residents who have made this country their home," he said. "We are a better society when we stand united in empowering others to reach success through immigration reform."
New York City Mayor Bill de Blasio said, "Cities are united, and we will fight for immigration reform in the courtroom, in Congress and in our communities."
Chicago Mayor Rahm Emanuel said, "The delay in implementing the executive actions harm not only immigrant families, but also our cities and our country, as everyone benefits tremendously from the economic, cultural and civic contributions of our immigrant communities."
Obama's orders would expand deferred deportation for parents of U.S. citizens, and for immigrants brought to the country as young children. It would affect an estimated 5 million immigrants.
A study by the Migration Policy Institute found a higher percentage of undocumented immigrants in Utah could benefit from the presidential order than in any other state. It estimated that 55 percent of Utah's undocumented population could be shielded from deportation, about 48,000 people.
Utah is among the 25, mostly Republican-led states that sued initially in federal court in Texas arguing that Obama's actions are unconstitutional because they bypassed Congress.
Also earlier, former Salt Lake City Police Chief Chris Burbank had also joined in a friend-of-the-court brief by the Major Cities Chiefs Association attacking that lawsuit and defending Obama's actions.