Just conducting DOS business on her personal email account (and server) was and is a big deal because it demonstrates uncommon arrogance and incredibly poor judgment, but a couple of Inspector Generals think she might have been using it inappropriately for sensitive and classified information and has asked the Justice Department to open a criminal investigation to find out. It is indisputably illegal to use unclassified email systems for classified information and sensitive information has to be encrypted on unclassified systems (doesn't matter if it's encrypted or not for classified - that's flat out illegal on unclassified systems) - and it doesn't matter if you're Secretary of State or your name is Hillary Clinton. Will the Obama Justice Department have the guts to open that investigation? Personally, I doubt it.
This is a big deal.
This is a big deal.