The Archdiocese of Washington is suing Metro for rejecting this ad. (N/A/Archdiocese of Washington)

The Archdiocese of Washington is suing Metro after the transit agency rejected an ad for the organization's annual "Find the Perfect Gift" charitable campaign, which features a biblical Christmas scene.

In the lawsuit, filed in U.S. District Court on Tuesday, attorneys for the archdiocese argue that Metro's ban on subway and bus ads that "promote . . . any religion, religious practice or belief" has infringed on the organization's First Amendment rights.

"The rejected ad conveys a simple message of hope and an invitation to participate in the Christmas season," archdiocese spokesman Ed McFadden said.

The banner ads, designed to be placed on Metrobus exteriors, are relatively minimalist in their design. The display highlights the phrases "Find the Perfect Gift" and "#PerfectGift," and includes a link to the campaign's website, which encourages people to attend Mass or donate to a Catholic charitable groups. The words of the ad are overlaid on a tableau of a starry sky; in the corner are three figures bearing shepherd's rods, along with two sheep.

In the lawsuit, the archdiocese argues that the ad posters "contain no explicit references to religion, religious practice, or belief." McFadden noted that Metro's policies allow much more latitude for Christmas-themed ads that are commissioned by commercial entities seeking to get people to buy their products.

"If Christmas comes from a store . . . then it seems [the Washington Metropolitan Area Transit Authority] approves," McFadden said. "But if Christmas means a little bit more, WMATA plays Grinch."

The archdiocese is asking a judge to declare that Metro's ban on religious ads infringes on the Catholic organization's freedom of speech and religion, and it wants the court to force Metro to accept the ad within the next week.

Metro does not comment on pending litigation, but spokesman Dan Stessel said the archdiocese is free to submit another advertisement free of religious imagery.

"Metro is not in a position to provide design guidance; however, if another version is submitted, it will be considered," Stessel said.

The dispute is the latest legal fight prompted by the transit agency's aggressive enforcement of stringent guidelines, adopted in 2015, governing what can be advertised on trains, buses and inside stations.

In the past year, Metro has been sued by the American Civil Liberties Union, an abortion provider, People for the Ethical Treatment of Animals, controversial author Milo Yiannopoulos and an Egyptian human rights advocate — all because their respective ads were rejected under the 2015 policy.

The sweeping clampdown on any ads that could be considered politically or socially charged is a significant shift for the transit agency. For years, the agency's policy was relatively lax. Since the 1980s, the transit system's stations, trains and buses have played host to ads that mocked President Ronald Reagan, criticized the Catholic Church, claimed that abortions resulted in breast cancer and promoted the legalization of marijuana.

Then, starting in 2012, Metro did an about-face. Transit agency officials rejected several ads that featured images considered intentionally incendiary and offensive to Muslims. Officials feared that posting the ads would spark violence or terrorism. (That fear wasn't without basis. When the same images were displayed at a 2015 event in Texas, the venue was attacked by two gunmen.)

A legal back-and-forth ensued, and in 2015, the Metro board instituted broad changes to the agency's advertising policy. It banned "issues-oriented" advertising, as well as anything related to religion or politics, as part of an effort to avoid legal wrangling altogether.

In recent months, Metro officials have defended the stance with a simple argument: They're merely enforcing the policies that were approved by the board two years ago. If people want a different policy, they say, they need to go to the Metro board.

Chairman Jack Evans said Tuesday that the policy serves its purpose of protecting the system while still allowing free speech.

"I don't have any interest in revisiting the policy," he said.

But in the lawsuit, attorneys for the archdiocese argue that Metro enforces the policy haphazardly, allowing, for example, ads by the Salvation Army, a Protestant charitable group. Metro also has recently approved posters that promote yoga and espouse the practice's benefits as a means to "an inner journey of self-discovery" and "acknowledgment of one soul to another," the archdiocese said.

They also note that they successfully advertised with Metro in the past, commissioning posters in the system in spring 2015 — months before the new policy was implemented — that "highlight[ed] the importance of the Sacrament of Reconciliation during the liturgical season of Lent."

The ad submitted to Metro for the most recent campaign was far less explicitly religious than a similar promotional display that will appear on bus shelters around the region that are not owned by Metro. Those ads quote the Gospel of Luke, telling passersby: "Behold, I proclaim to you good news of great joy."

Metro's rejection of the Christmas-themed ad comes as officials are scrutinizing other parts of the agency's advertising policy as part of an effort to raise cash to help fund operations. Board members have offered tepid support for a proposal to sell station naming rights for multimillion-dollar fees, although there has been no official action.