You’re planning an advertising campaign that’s going to run on subways and buses and in other media space controlled by a state or local transit authority. Do you have a First Amendment right to run whatever you want or can these authorities pick and choose what types of ads they accept? This was the issue that was recently before the United States Court of Appeals for the D.C. Circuit.

The Archdiocese of Washington sued the Washington Metropolitan Transit Authority (“WMATA”) after WMATA refused to run one of the Archdiocese’s ads on the outside of city buses. The ad depicts a starry night and the silhouettes of three shepherds and sheep on a hill facing a bright shining star high in the sky along with the words “Find the Perfect Gift.” The ad also includes a website address and a hashtag.

WMATA rejected the ad, saying it violated WMATA’s “Guidelines Concerning Commercial Advertising.” Specifically, the Guidelines prohibit, among other things, ads that “promote or oppose any religion, religious practice or belief.” WMATA had updated its Guidelines in 2015 to prohibit all issue-oriented ads, including ads related to religion.

Following Supreme Court precedent, the court held that WMATA was within its rights to establish rules that limit the types of advertising it accepts, so long as the rules are reasonable and don’t suppress a particular viewpoint. Here, the court said that WMATA’s rules were both reasonable and viewpoint neutral.

Responding to an argument from the Archdiocese that it wasn’t proper to accept ads for Christmas sales, but not for Christmas itself, the court wrote, “ads promoting Christmastime sales are not expressing a view on Christmas any more than a McDonald’s ad expresses a view on the desirability of eating beef that demands the acceptance of a contrary ad from an animal rights group.”

The important take-away from this case isn’t just about religious advertising, however. If you’re planning a transit campaign, it’s important to be aware of each transit system’s advertising guidelines before you get too far into creative development. They each typically have their own extensive rules about what types of advertising they will accept. In addition to often prohibiting issue-related advertising, they may prohibit the advertising of certain categories of products (such as guns, tobacco, or adult-themed entertainment) or the use of certain types of content (such as sexually-related imagery). You’ll also want to make sure you understand their pre-approval procedures as well, so you don’t get stuck with advertising space but no advertising to run.