Judy Clarke has been appointed to represent a number of unpopular defendants: Ted Kaczynski (the Unabomber), Susan Smith, Zacarias Moussaoui, Timothy McVeigh, Eric Robert Rudolph. And now she has been appointed to represent Jared Loughner. See Judy Clarke: Loughner's Lawyer Defended the Unabomber - TIMEJan. 12, 2011; Loughner’s Lawyer Is Called a Master Strategist, N.Y. Times, Jan. 10, 2011.
For a very interesting account of the representation of Kaczynski, see Michael Mello, United States v. Kaczynski: Representing the Unabomber, in Legal Ethics Stories (Deborah L. Rhode & David Luban eds., 2006), KF306.A4 L43 2006 at Reference Area.