Before Hillary Clinton ends her tenure at the State Department she'll deal with one final piece of unfinished business today—answering Congress's questions about the Benghazi attack. Clinton will appear before both the House Foreign Affairs and the Senate Foreign Relations Committees in a full day of hearings on the subject. She will be the only witness on Wednesday and because these are not intelligence committees, the hearing will be open to the public. C-SPAN will carry both hearings, beginning with the Senate at 9:00 a.m. ET.

Clinton will likely get her harshest treatment in the Senate, where several lawmakers, especially John McCain, have had harsh words for the administration's handling of the attack on the consulate. In particular, the committee will want to know about the security situation at the consulate, both before the attack on September 11 of last year, and the military and intelligence response after it was underway. Clinton has already said she accepts responsibility for the failures there, and will likely reiterate that today.

McCain is so determined to get answers that for the first time in his 26 years in the Senate, he's joined the Foreign Relations Committee for this term. His constant pushing on the subject has already scuttled the nomination of Susan Rice to be Clinton's replacement before it could happen, and there's no reason to think he'll go any easier on the actual sitting (but outgoing) Secretary. The other Republicans on the committee—Marco Rubio, fellow Arizonan Jeff Flake, and the new ranking members, Bob Corker—should have plenty of tough questions as well.

Today's hearings may also be the last time Clinton sets foot in the Capitol as Secretary of State. The nomination hearing for her replacement is scheduled for Thursday—complete with waterboarding jokes!—with an easy confirmation vote expected shortly thereafter. Once John Kerry is approved, Clinton is free to go and then its off to some much-needed R&R and then ... well, we'll worry about that in a few years.