Mrs Clinton is barred from Federal office.

Former United States Attorney General Michael Mukasey tells MSNBC that not only is Hillary Clinton's private email server illegal, it "disqualifies" her from holding any federal office.

Such as, say, President of the United States. Very specifically points to one federal law, Title 18. Section 2071.

For those of us who do not have United States Code committed to memory, here's what it says:

(a) Whoever willfully and unlawfully conceals, removes, mutilates, obliterates, or destroys, or attempts to do so, or, with intent to do so takes and carries away any record, proceeding, map, book, paper, document, or other thing, filed or deposited with any clerk or officer of any court of the United States, or in any public office, or with any judicial or public officer of the United States, shall be fined under this title or imprisoned not more than three years, or both.

(b) Whoever, having the custody of any such record, proceeding, map, book, document, paper, or other thing, willfully and unlawfully conceals, removes, mutilates, obliterates, falsifies, or destroys the same, shall be fined under this title or imprisoned not more than three years, or both; and shall forfeit his office and be disqualified from holding any office under the United States. As used in this subsection, the term œoffice does not include the office held by any person as a retired officer of the Armed Forces of the United States.

Yes, it explicitly states "shall forfeit his office and be disqualified from holding any office under the United States."