In a rare bow to outside pressure, Facebook Inc. (NASDAQ:FB) on Tuesday said it is reevaluating its policy in regards to offensive content aimed at women and girls.

The announcement follows a weeklong social media protest in which feminists and women’s groups had been targeting Facebook advertisers to let them know that their ads were appearing alongside misogynistic content. Ads for blue-chip companies such as American Express Co. (NYSE:AXP) often appear next to offensive, sometimes graphic memes that make light of rape and violence toward women. Facebook contends that some of the content is humorous in nature and therefore not actionable hate speech.

But a week into the #FBrape campaign -- which was launched by Women, Action & the Media (WAM, the Everyday Sexism Project and the activist Soraya Chemaly -- Facebook said it was reviewing the guidelines its moderators use to evaluate whether content should be removed. In a lengthy explanation posted on Tuesday, Marne Levine, Facebook’s vice president of global public policy, said the social network plans to work with legal experts and women’s groups to ensure that its policies reflect best practices.

“In recent days, it has become clear that our systems to identify and remove hate speech have failed to work as effectively as we would like, particularly around issues of gender-based hate. In some cases, content is not being removed as quickly as we want. In other cases, content that should be removed has not been or has been evaluated using outdated criteria. We have been working over the past several months to improve our systems to respond to reports of violations, but the guidelines used by these systems have failed to capture all the content that violates our standards. We need to do better -- and we will.”

Jaclyn Friedman, executive director of WAN, welcomed the news. “We are reaching an international tipping point in attitudes towards rape and violence against women,” she said in a statement. “We hope that this effort stands as a testament to the power of collaborative action.”

Some free-speech advocates, however, did not seem happy with the announcement. On Twitter Wednesday, Jillian York of the Electronic Frontier Foundation got into a few arguments over whether or not Facebook should be in the business of policing its users’ content beyond what the law requires.

Facebook, for its part, acknowledged that balancing free expression with community respect raises “complicated challenges,” particularly when a billion-plus users are thrown into the mix.

Read Facebook’s full response to the #FBrape campaign here.

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