After the Washington Metropolitan Area Transit Authority refused to run Catholic ads on its buses and trains that depicted photos of shepherds and the website FindThePerfectGift.org in November, the Archdiocese of Washington sued – but a federal judge appointed by President Obama upheld the Metro's Catholic ad ban.

The following is the advertisement that the Archdiocese of Washington sought to display:

The website on the ad, FindThePerfectGift.org, offers information about Mass schedules and holiday traditions.

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The transit authority said it wouldn't run the advertisement because it bans religious-themed advertising. Transit attorneys claimed there are two aspects of Christmas: one secular and the other religious.

"Advertisements involving secular symbols of the holiday – reindeer, the Yule log, the Christmas trees ... address the secular half of Christmas," the transit authority explained. "Overtly religious ads, like those featuring religious imagery like a scene of shepherds and the Star of Bethlehem ... address the religious half of Christmas.

"Here, WMATA has simply prohibited advertisements related to the subject of the religious half of Christmas, but not the secular half," it continued. "That is not viewpoint discrimination."

The archdiocese noted that the transit authority regularly runs ads for the Salvation Army, the Book of Mormon musical and a yoga school.

Judge Amy Berman Jackson supported the transit authority's decision to ban the ad in December.

"Given [Washington Metropolitan Area Transit Authority's] concerns about the risks posed by issue-oriented ads, including ads promoting or opposing religion, its decision was reasonable," Jackson wrote. "The regulation is reasonably aligned with WMATA's duty to provide safe, reliable transportation ... and it does not violate the First Amendment."

The archdiocese appealed the decision. Now First Liberty Institute and the Ethics and Public Policy Center have filed a filed a friend-of-the-court brief in the U.S. Court of Appeals for the District of Columbia supporting the archdiocese. The brief argues that the transit authority violated the Constitution.

"WMATA prohibited the Archdiocese's advertisement not because it referred to Christmas, but because it sought to convey a religious viewpoint message emphasizing that Christ is the reason for the season," Kelly Shackelford, president, CEO and chief counsel to First Liberty said Tuesday.

"What’s really shocking is that WMATA in this case said there were 'two halves' of Christmas, the religious half and the secular half. But only messages relating to the 'secular half' were welcome on their buses. Evidently, WMATA can now accept Christmas advertisements about Santa Clause, but rejects the nativity; it accepts the three French hens, but not three wise men."

The brief states: "WMATA's notion of a 'secular half' of Christmas is itself a viewpoint on a religious holiday. By permitting advertising promoting this 'secular half,' WMATA is allowing a very definite viewpoint about the meaning of Christmas to be expressed on its buses. If the 'perfect gift' at Christmas is an iPhone or a new Mercedes-Benz, WMATA will happily take the advertiser's money. But the Archdiocese's advertisements, which tells viewers that the perfect Christmas gift is Christ Himself, is excluded. WMATA thus permits advertisements that invite the public to secularize a holiday sacred to Christians, while it excluded an advertisement designed to counteract that message and the cultural trend that goes along with it."

First Liberty Institute and the Ethics and Public Policy Center say the transit authority is engaging in "blatant viewpoint and religious discrimination." The groups called on the district court to reverse its order allowing the transit authority to discriminate against the Catholic ads.