Via Weekly Standard: 

Since FBI director James Comey blasted Hillary Clinton for her deceptions about mishandling classified information and yet inexplicably announced he was recommending no charges be brought against her, there's been a lot of speculation about how this could be justified. In his own words, Comey called her "extremely careless," but the legal standard for criminal activity is "gross negligence". There's been a lot of headscratching about the the distinction. Further, both "gross negligence" and being "extremely careless" imply that Hillary Clinton's actions were unintentional on some level.

However, in 2000, Hillary Clinton told Stan Lee (yes, of Marvel Comics fame) at a dinner party, "As much as I've been investigated, why would I ever want to do email?" The video provides more than a strong suggestion that Clinton's email arrangement was deliberately designed to evade accountability from investigators. That strikes me as more than simple negligence, and speaks directly to intent.