The ACLU and conservative commentator Milo Yiannopoulos are not usually on the same side of an issue, except when it comes to free speech on the subway system in Washington, D.C.

The company owned by the former Breitbart news editor, MILO Worldwide and the American Civil Liberties Union, along with a women's health collective called Carafem and the nonprofit People for the Ethical Treatment of Animals, filed a lawsuit Wednesday in federal court against the Washington Metropolitan Area Transit Authority. The lawsuit claims the D.C. subway system, called Metro, violated each groups' First Amendment rights by refusing to run their advertisements. Metro's advertising restrictions are “explicitly viewpoint-discriminatory,” the lawsuit claims.

“The ACLU and Mr. Yiannopoulos probably do not find themselves allied frequently, but they are allied on the First Amendment,” said Stephen Meister, a partner in the New York office of Meister Seelig & Fein, who represents MILO Worldwide.