Biden claimed he was once arrested for trespassing at the Capitol at age 21 foxnews.com

In a 2007 appearance on David Letterman, then-Sen. Joe Biden, D-Del., claimed he was arrested at the U.S. Capitol when he was 21 years old.
Letterman asked Biden what it was like to walk into the U.S. Senate chamber after being elected at the age of 29.
Biden said he had actually walked into the Senate chamber when he was 21 and got arrested.