David Letterman’s accused extortionist, Robert “Joe” Halderman, is “a great human being “ but “he's positioned as a bad guy,” says friend and former co-worker Dr. Bob Arnot. “No one’s standing up for Joe,” he continues—so, certainly, Halderman must be glad that Arnot went on Good Morning America to discuss his friend getting “enraged” over “a very passionate embrace” he witnessed between Letterman and Stephanie Birkitt in August. More: