This guy knows of what he speaks...
http://www.nationalreview.com/article/455202/hillary-clinton-email-investigations-trump-justice-department-revives-motive-criminal-intent
This was a straightforward case of criminal intent. Negligence was the fallback position — for a prosecutor, an “even if” theory, as in: “Even if you’re not convinced by our overwhelming evidence of Clinton’s willfully illegal retention and transmission of classified information, you can still comfortably find her guilty if you conclude that she was grossly negligent — which, as the judge will tell you in his instructions, simply means ‘extremely careless.’”
http://www.nationalreview.com/article/455202/hillary-clinton-email-investigations-trump-justice-department-revives-motive-criminal-intent