With allegations escalating that Facebook actively suppresses politically conservative news stories, the company has denied it's taking a political bend.
"We take these reports extremely seriously, and have found no evidence that the anonymous allegations are true," wrote Tom Stocky, a member of Facebook's Trending Topics team, in a post . "Facebook is a platform for people and perspectives from across the political spectrum."
Stocky's comment came after allegations surfaced in Gizmodo, a tech blog, that Facebook employees "routinely suppressed news stories of interest to conservative readers" from the social network's section highlighting the site's top trending stories.
Citing an anonymous source who is said to have worked on the project, Gizmodo reported that Facebook kept stories about Mitt Romney, Rand Paul and the Conservative Political Action Conference from getting a spot in the Trending topics list even though they had garnered enough attention on the site to warrant the listing.
The report also alleges that Facebook's so-called news curators said they were told to inject some stories into the Trending list even if they weren't popular enough to be there organically. Gizmodo also alleges that Facebook told the curators to not put stories about the company itself in the list.
It didn't take long before a politician became involved.
Earlier today, U.S. Senator John Thune (R-SD), chairman of the Senate Committee on Commerce, Science, and Transportation, sent an open letter to Facebook CEO Mark Zuckerberg, asking him to answer questions about the allegations.
"Social networks such as Facebook are an increasingly important source of news for many Americans and people around the world," he wrote. "Indeed with over a billion daily active users on average, Facebook has enormous influence on users' perceptions of current events, including political perspectives."
Thune questioned who is ultimately responsible for approving Trending topics; have news curators excluded stories related to conservative views, and are there records of curators' decisions?
He also asked for a copy of Facebook's internal Trending topics guidelines and for descriptions of the company's training policies.
This issue, according to Dan Olds, an analyst with The Gabriel Consulting Group, could affect how many people get their daily doses of news, as well as the social network itself.
"I don't see anyone leaving Facebook over this issue, but I think it does put a dent into its ambition to become a major news source," he said. "I think a significant number of people at least get their news headlines from Facebook, and now at least a portion of those people are going to wonder if those topics are actually trending news, or just something Facebook wants them to think is trending news."
Facebook's Stocky noted in his post that guidelines for Trending topics are constantly under review but that they do permit reviewers to "make topics more coherent -- for instance combining related topics into one.
"Facebook does not allow or advise our reviewers to systematically discriminate against sources of any ideological origin and we've designed our tools to make that technically not feasible," he added. "At the same time, our reviewers' actions are logged and reviewed, and violating our guidelines is a fireable offense."
Olds, though, said Facebook needs to more fully address the issue than to have just one employee post a response on his own Facebook page.