“We are always looking to improve our policies to make sure they both promote free expression and keep our community safe, and we will be engaging with publishers and other members of our global community on these important questions going forward,” a Facebook spokeswoman said.

The frequency with which Facebook needs to respond to questions over its media role has increased over the past 18 months. In May, the company had to grapple with reports that some editors working on its “Trending Topics” section — a portion of the site in which Facebook displays some of the most-talked-about stories on the network — were suppressing conservative political content.

Facebook last month laid off the Trending Topics team and said it would rely solely on algorithmic decision-making to surface trending stories across the site. In the weeks since, some have called for Facebook to rethink that stance, as several fake news stories have more prominently appeared in the section.

Image A.J. Chavar, a New York Times journalist, reposted the Times’s article about Facebook removing posts including the Vietnam War-era photo showing a naked girl escaping napalm bombing. Facebook quickly removed Mr. Chavar’s post, citing Facebook community standards that restrict the display of nudity. Credit... AJ Chavar

Last year, Facebook also had to revise its community standards after photos of women breast-feeding were removed from their Facebook pages. And the company apologized in May after it blocked a photo of a plus-size model for being “undesirable.”

Facebook’s editorial influence reaches far beyond Trending Topics. The company, with 1.71 billion members worldwide, is continuously refining and updating the algorithms that control the News Feed, the stream of status updates, news articles, photos and videos that most of its users spend the most time interacting with. Those changes affect the type of content people see more frequently — photos from friends and family, for instance, instead of news stories — which can have an effect on what people are sharing across the network.

Many of the world’s largest publishers, from The New York Times and The Guardian to Vice and BuzzFeed, also increasingly rely on Facebook to communicate with the social network’s users. A growing number of media companies and analysts have raised concerns that Facebook may hold too much sway over how information is distributed.