I tried updating my post but because this post was flagged away it seems to have duplicated somewhere else: https://news.ycombinator.com/item?id=12037507 -- This article explains it a bit, it's also light on the details. If you read the Judicial Watch testimony of her staffers, a lot of them touch on this.
Bah did the link in my comment not work? I tried updating my original comment to link to http://www.politico.com/story/2015/03/state-department-email... but now there's two versions of my comment, one pre-edit in this chain and one post-edit in another chain I can't find. This article is heavily biased, I think, but it mentions the post Powell rulings. In the Judicial Watch testimony of Cheryl Mills she mentioned the post Powell decisions.