The Washington Metropolitan Area Transit Authority (WMATA) is facing a lawsuit for denying advertising space to Wallbuilders, a Christian organization. The plaintiff alleges that WMATA is violating its First Amendment rights and displaying anti-Christian bias in its refusal to allow the organization to advertise in its facilities.

What makes this turn of events even more noteworthy is that the American Civil Liberties Union (ACLU) is representing the organization. In a press release, the ACLU argued that government entities like the WMATA cannot discriminate against speech based on viewpoint:

The lawsuit argues that these ad guidelines violate the First Amendment, which prohibits government agencies from discriminating against private speech based on their viewpoint or from imposing rules that aren’t applied consistently. The lawsuit provides many examples of ads about controversial issues that WMATA has accepted, such as recent ads demanding Supreme Court term limits along with ads demanding transparency in hospital prices. WMATA has also accepted ads with religious content, such as an ad for The Book of Mormon musical, which harshly lampoons the Mormon Church and religion in general. The lawsuit shows how the guidelines inevitably lead to discrimination based on advertisers’ viewpoints and are necessarily applied in an arbitrary and unreasonable manner.

Arthur Spitzer, senior counsel at the ACLU’s D.C. office, referred to the WMATA’s actions as “selective censorship” and argued that the state “cannot arbitrarily decide which voices to silence in public forums.”

Jeremy Dys, senior counsel at the First Liberty Institute, another organization involved in the lawsuit, said:

“Rejecting a faith-based advertising banner by labeling it an ‘issue ad,’ while accepting other ads such as those promoting a ‘Social Justice School,’ ‘Earth Day,’ and the highly controversial idea of terms limits for Supreme Court justices, is clearly hypocritical, discriminatory, and illegal. WMATA must support the freedoms provided in the First Amendment rather than silence Americans through censorship.”

At the heart of this debate is the fundamental principle of free speech. Public forums should be subject to the highest level of First Amendment protection, meaning that a government entity has no business picking and choosing which viewpoints are allowed to be displayed in an advertising space.

This is not the first time the ACLU has clashed with the WMATA. A 2017 lawsuit listed several instances in which the entity had discriminated against other organizations based on viewpoints.

This free speech lawsuit is the second filed by the ACLU that challenges WMATA’s advertising guidelines. The 2017 lawsuit, ACLU et al. v. WMATA, documents how WMATA has discriminated against a variety of viewpoints, including an abortion pill ad from the women’s health care collective Carafem, an ACLU ad seeking to display the text of the First Amendment in several languages, an ad for Milo Worldwide LLC (the company of conservative commentator and writer Milo Yiannopoulos), and an ad by People for the Ethical Treatment of Animals.

The ACLU is a left-leaning organization that has typically advocated for left-wing causes. But the group has also shown a willingness to represent people and organizations who hold beliefs with which the organization’s members might disagree. Recently, it was announced that the ACLU would be defending the National Rifle Association before the Supreme Court. In this case, they are standing on principle, taking the government to task for ignoring the First Amendment.