As herself, she gave on-air reports from the sites of the Winter Olympics in 2002 and in 2006. In all, she made more than 250 appearances on the program between 1996 and 2008. By the time of her final appearances on the show, in the autumn of 2008, she had completed her law school education. In addition to her appearances on "Late Show with David Letterman", Birkitt co-hosted "The Tony Mendez Show", a spin-off program with Tony Mendez (also known as "The Cue Card Boy") that was hosted on the "Late Show" website. Birkitt described her relationship with Letterman in an interview with the "Fort Worth Star-Telegram" in 2004. In the article, titled "Letterman Aide is Dave's Main Tease", Birkitt stated, "[Letterman is] just playful. We play catch sometimes in the office, and we all go to screenings together. We eat food together, we sit around and watch TV together and goof on people. And he teases me in real life, too, but I give it back a lot more in real life." In a statement released on October 7, 2009, Letterman's production company Worldwide Pants announced that Birkitt had been placed on a "paid leave of absence" from the "Late Show". On October 1, 2009, Letterman announced on-air that he had been the victim of an extortion attempt in which an alleged blackmailer—since identified by police as CBS television producer Joe Halderman—threatened to reveal that Letterman had engaged in sexual affairs with multiple female employees. Letterman admitted on television that the allegation was true, but did not reveal the names of, or any identifying information about the female employees. Soon afterward, the extortionist was identified by media as a former lover of Birkitt, and anonymous sources alleged that Birkitt and Letterman also had a sexual relationship. Birkitt reportedly was neither aware of, nor involved in the blackmail attempt. According to CBS News, Birkitt and the CBS News producer Joe Halderman lived together in Halderman's home in Norwalk, Connecticut, until August 2009, when she reportedly moved out; she was also romantically linked to Letterman during the same time. The "New York Post" broke a story on October 6 that Birkitt had an affair with Letterman, which continued during her relationship with Halderman. Copies of entries in Birkitt's diary, as well as emails between her and Letterman, were reportedly the basis of the blackmail evidence allegedly placed in Letterman's car by Halderman.