Vice President Joe Biden officiated over a wedding for a same-sex couple Monday, his first time officiating a wedding after obtaining a temporary certification from the District of Columbia. Biden apparently got the certification especially to marry two White House staffers, Brian Mosteller and Joe Mahshie. According to his office, he married the pair at the Naval Observatory in a small ceremony open only to the grooms’ families. Biden posted a picture of the event on Twitter,writing, “Proud to marry Brian and Joe at my house. Couldn’t be happier, two longtime White House staffers, two great guys.” Biden came out in favor of same-sex marriage back in 2012.