'I didn't think what I was doing was wrong'
8 July 2013 Last updated at 12:08 BST
Jack Abramoff is a former lobbyist, businessman, movie producer and writer. He went to prison for conspiracy to bribe US congressmen and senators.
He gave them meals, gifts, trips and sports tickets in exchange for political sway that helped him secure millions in federal grants and funding for his interests.
He told the BBC: "I didn't think what I was doing was wrong, that's the biggest problem.
"I was deeply involved in a system that was highly immoral. I shouldn't have done it and [at the time] I couldn't see it."