Stephen Colbert welcomed "the thickest head of hair in the criminal justice system" (Andrew Napolitano, FNC analyst and co-host of FNR show "Brian and the Judge,") to The Colbert Report last night to discuss his book, "A Nation of Sheep." After a traditional Colbert rant, a certain FNC host was mentioned when Napolitano asked, jokingly, "Who do you think you are, Bill O'Reilly?" Colbert responded: "Sometimes."

But at the end of the interview, as Napolitano was riled up about freedom vs. government, he seemed to forget where he was: "That's why we have a constitution! To restrain the government, Bill. I mean, Stephen."