Officially, the vice president was sorry for forcing his boss's hand -- but that "apology" never occurred and should never have been fabricated by White House staff.
Vice President Joe Biden never apologized to President Obama for getting a "bit over his skis" in endorsing gay marriage before the president did -- and according to very senior White House sources, Obama didn't ask for or want an apology from Biden.
But google "Joe Biden", "apology", and "gay". On May 10, 2012 the official White House position -- as fed to the media -- was that Joe Biden apologized to the president.
What did happen is that Obama White House staff and campaign advisers went nuts and angrily denounced Biden for triggering what they thought would be a gay marriage political nightmare after comments on a Sunday morning talk show. Jay Carney, spokesman for the president and former spokesman for Biden, was widely acknowledged to be an exception to the tension and was working hard to bridge the mutually angry camps.
The heat was so strong that Biden staff scrambled to construct a gesture, which was a falsehood, that Biden apologized to the president for getting ahead of him on gay stuff. Biden staff put out word that Biden apologized -- but the truth of this matter is that never happened.
Or did it? Biden himself never said "sorry" to the president for his principled stand on the leading civil rights issue of the time. That would be a bit like Lyndon Johnson tucking it in and apologizing to JFK for being about nine steps ahead of the Kennedy clan on black civil rights in the country (which LBJ was).
However, when staff do something in the name of the principal for whom they work -- the question is whether that constitutes truth or not. In political or financial scandals, one of the techniques that politicians frequently use is to blame the transgression on an aide working for the pol, arguing that the principal had no knowledge of the illegal act. However, when things are going smoothly and well, Senators and Congressmen count on their aides to generate legislative and political successes for which they can take credit in their own name.
Very little in the Congressional Record for that matter, that is the digest of all that officially transpires on the floor of the House of Representatives and Senate, actually happens. There are tributes, commendations, long speeches that read as if they were given and which appear in the record -- but even a bleary-eyed replay of C-Span video will never yield the commentary being given.
Typically, a legislative assistant will write a speech on some topic for his boss, a senator or representative, let's say on the subject of stopping Iran's nuclear program. Then the legislative director will approve the speech, and it will be transmitted by the staff member down to the floor clerk for inclusion in the Congressional Record. The senator or House member, on most occasions, never sees the commentary that will appear under his or her name. The system works on trust and the subordinated credentialing of staff who are given the authority to speak, think, and write in the name of their employer.