The suit claims the city denied the paid billboard because it doesn't allow "issue" and "advocacy" ads at the airport. Also listed as a defendant is Clear Channel Outdoor Holdings Inc., which manages the ad space at Philadelphia International.
But the NAACP claims in its suit that other issue billboards have appeared at the airport, including those from the World Wildlife Federation, the Foundation for a Better Life and the United Service Organizations.
Robert Brooks, director of the NAACP's criminal-justice program, said the billboard had been denied at other airports, like San Francisco's and Washington, D.C.'s, for similar reasons. However, the NAACP is not filing lawsuits against those cities because "they seemed consistent with what they were doing and Philadelphia did not," he said.
When asked whether such a billboard would be appropriate for first-time visitors to the city, Brooks said, "Absolutely."
"We are a country that locks up more people than any other country in the world, and if I was traveling somewhere, I would want to know that when I get there," he said.
Mary Catherine Roper, staff attorney for the ACLU, said the case was a "classic issue of freedom of speech."
"When the government is deciding who gets to speak and who doesn't get to speak, that really shouldn't turn on whether the subject of the speech is controversial," Roper said.
Mark McDonald, press secretary for the Mayor's Office, declined to comment on pending litigation.