(RNS) — Metroplex Atheists, a Texas-based nonprofit advocating for the separation of church and state, filed a federal lawsuit against the city of Fort Worth, Texas, after being denied the right to hang banners promoting an event against Christian nationalism. The group argues the rejection was discrimination and a violation of free speech.

In May, the city manager’s office denied Metroplex Atheists’ application to display advertisements on the city’s lampposts from Aug. 8-22. Assistant City Manager William Johnson declared the event noncompliant with the city’s public banner policy because it was not of a “magnitude to qualify.”

Since 1998, the city has allocated free advertisement spots to nonprofits to promote their organization or any events as long as they are open to the public, of common interest to the general community and held in Fort Worth.

Planned for Aug. 26 at the Fort Worth Botanic Garden, the Metroplex Atheist event is intended to highlight what the group sees as the dangers of Christian nationalism and to argue that prayer should be kept out of public schools. Guests include Bradley Onishi, a religion scholar and author of the book “Preparing for War: The Extremist History of White Christian Nationalism — and What Comes Next,” and the Rev. Katie Hays from the nearby Galileo Church.

“Free speech is free speech, whether or not the government likes that speech or certain members of the community object to it,” said Geoffrey T. Blackwell, the author of the complaint and a legal counsel for American Atheist.

The organization, along with the American Humanist Association and the Glast, Phillips & Murray firm, are representing Metroplex Atheists in the case. Fort Worth defendants include Mayor Mattie Parker and council members.

Downtown Fort Worth, Texas. Photo by Fallon Michael/Unsplash/Creative Commons

In the complaint, the organization contends that the city’s decision to deny the banner request violates the First Amendment. The complaint alleges the city favors pro-religious speakers, noting it regularly allows banners for Texas Christian University and has authorized a campaign for Kenneth Copeland Ministries’ Southwest Believers Convention in the past.

In a statement sent to Religion News Service via email, the Fort Worth legal department said: “The City is aware of the lawsuit, believes that it acted appropriately and will defend its position in Court.”

In July 2019, Metroplex Atheists ran bright yellow “In NO God we trust” banners on the city’s lampposts to promote the group’s annual event in the Botanic Garden. The banners gained national attention and sparked sparked vehement criticism. Some banners were vandalized.

The mayor at the time, Betsy Price, reacted in a tweet, saying she was appalled by the campaign but that, despite disagreements, the organization followed procedures.

Metroplex Atheists hopes to obtain the right to run this year’s campaign and reassurances that Fort Worth won’t be able to discriminate against the group in the future. The organization is also asking for damages and attorney fees.