Facebook announced Monday it was sending employees out for retraining and would discontinue some of its practices as it sought to defend itself against charges of political bias against conservatives.

The online giant denied that it’s shown “systematic political bias,” but admitted employees played a bigger role than previously acknowledged in determining what news is highlighted in the trending topics section.

Facebook also acknowledged that rogue employees may have unintentionally discriminated against conservative stories or even acted with malice in “isolated improper actions.”