has declared — again — that its Trending Topics section is free of any political bias or manipulation. However, the company says it is still changing the way it finds articles for the news section.
First, the declaration: Facebook General Counsel Colin Stretch wrote in a blog post that the company met with Sen. John Thune, chairman of the Senate Commerce Committee, last week to discuss its trending news section, which came under fire after Gizmodo reported that Facebook employees were quashing conservative news stories from appearing on the list.
Facebook said at the time that this was not true. It reiterated that Monday in an open letter to Thune, in which it highlighted an internal Facebook investigation. "Our investigation has revealed no evidence of systematic political bias in the selection or prominence of stories included in the Trending Topics feature," the letter reads.
Thune seemed content with what Facebook showed him: "The seriousness with which Facebook has treated these allegations and its desire to serve as an open platform for all viewpoints is evident and encouraging," he responded in a statement.
But he also noted this: "We now know the system relied on human judgment, and not just an automated process, more than previously acknowledged."
Facebook has long said that human editors would do things like "approve" stories and write headlines, but not explicitly select which stories appear. It's still not entirely clear how much impact human editors have on what appears in Trending Topics versus what doesn't, but Thune's statement says quite clearly that humans are pretty heavily involved.
The result of all this is that Facebook now says it is revamping how editors find trending stories. While the company says it found no "systematic" biases, the process wasn't perfect.
"We could not fully exclude the possibility of isolated improper actions or unintentional bias in the implementation of our guidelines or policies," Stretch wrote.
In addition to some obvious updates, like retraining the human editors who have a hand in Facebook's trending section, Facebook says it will abandon a handful of automated tools it used to find and categorize trending news in the past.
For example, it will no longer use its "1K list," a group of 1,000 websites it used to help verify headlines. It will also abandon a list of top publications, including the New York Times and CNN, it initially used to assign a level of importance to a trending topic.
So it's essentially a way for Facebook to clean up how it vets topics and headlines, although we're not entirely sure if there's a new mechanism in place to determine the validity of breaking news. We've asked Facebook and will report back what we find.
Update: We spoke with a Facebook spokesperson and got a little more info. Here's what we were able to understand.
—By Kurt Wagner, Recode.net. Noah Kulwin contributed to this story.
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