Joking that it was so much fun he had to do it again, Barack Obama became the third U.S. president to take the oath of office a second time because of concerns over the initial swearing-in.
U.S. Supreme Court Chief Justice John Roberts again delivered the oath to Obama on Wednesday night in the White House Map Room, a day after the president took it in front of more than 1.5 million people on the steps of the Capitol in Washington.
Several of the president's aides, a handful of reporters and a White House photographer attended the brief ceremony. No television camera crews or news photographers were present, but the ceremony was audiotaped.
Obama didn't use a Bible for the second oath, but it is still binding.
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Obama joins Chester Arthur and Calvin Coolidge as U.S. presidents who have had to retake the oath of office because of unusual circumstances.
Arthur, who served from 1881 to 1885, was sworn in by the chief justice of the New York Supreme Court at his home in a private ceremony following the assassination of former president James Garfield. Arthur was sworn in a second time by the chief justice of the U.S. Supreme Court two days later at the Capitol.
In Coolidge's case, he took the oath of office at his father's Vermont home following the death of former president Warren Harding. Coolidge's father was a justice of the peace and administered the oath. Concerns about the jurisdiction of Coolidge's father led to Coolidge taking a second oath later in Washington.
http://www.cbc.ca/world/story/2009/01/22/obama-oath.html______________________________________________________________________
In 1929 Chief Justice William Howard Taft administered the oath of office to Herbert Hoover. Taft had been a President. He’s the only President then to serve as Chief Justice to administer the oath of office to a President.
But when Taft read the oath of office he made a mistake. In stead of asking Hoover to preserve, protect and defend the Constitution he said, “preserve, maintain and defend.” Well, it seemed to have just passed by, but this was broadcast on the radio. A 13 year old student heard this and she said that’s wrong. She had memorized the oath. She wrote Taft a letter. She said you goofed. He wrote her back and said you're quite right. In fact she said, you said “preserve, maintain and defend.” He said you’re right, I didn’t get it right, but I didn’t say it that way. I said, “preserve, maintain and protect.”Well she was sure she was right, and sure enough, the news media checked their recordings and she was right and Taft was wrong twice.
http://fpc.state.gov/114510.htm