What motivates a lawyer to defend a Tsarnaev, Castro, or Zimmerman?

To the contrary, I often call my life’s work “the guilty project.” Criminal defense is, for the most part, defending the factually guilty — people who have done something wrong, though maybe not exactly what is alleged.

That works for me because, as it happens, I like guilty people. I prefer people who are flawed and complicated to those who are irreproachable. As legendary American lawyer Clarence Darrow put it more than 80 years ago: “Strange as it may seem, I grew to like to defend men and women charged with crime. . . . I became vitally interested in the causes of human conduct. . . . I was dealing with life, with its hopes and fears, its aspirations and despairs.”

Defense lawyers try to find the humanity in the people we represent, no matter what they may have done. We resist the phrase “those people” because it suggests too clear a line between us and them. Clarke has managed to do this with some of the most notorious criminals of the past two decades, including “Unabomber” Ted Kaczynski. “Even if it’s the smallest sliver of common ground, Judy’s going to be able to find that,” said Kaczynski’s brother, David. “There’s no doubt in my mind that Judy saw my brother’s humanity despite the terrible things he’d done.”