At his excellent law blog Defending People, Mark Bennett answers The Question: “Why do you defend people who you know to be factually guilty?”
Actually, he answers seven times, after thoroughly dissecting the question itself. I’m going to abstract here, but you should absolutely read the whole thing.
I. The Sixth Amendment Answer
We swear to uphold the U.S. Constitution. Part of that Constitution, the Sixth Amendment, requires that everyone accused of a crime—not just everyone who a good lawyer thinks deserves it—have effective representation.
II. Cops lie [Scott Greenfield]. Prosecutors cheat. Juries screw up. Some laws should not exist, and other laws provide punishments that are grossly out of proportion….
If I take it upon me to decide who is guilty, it’s almost certain that sometimes my judgment would be wrong .
III. Jesus set the example—when called on to judge the woman caught “in the very act” of a capital offense, he defended her. Successfully.
IV. We all deserve at least one person on the damn planet willing to stand there next to us and fight on our behalf.
V. Any approximation of justice that the system creates comes about only because there are people fighting on both sides.
VI. The John Wayne Answer: When a person comes to me for a defense, with the vast power of the government arrayed against him, no matter what he did before he is the underdog now. I stand up for the underdog. I protect the weak from the strong. Every man needs a code to live by, and that is part of mine.
VII. Criminal defense is a way of looking at the world….
In other words, wir können nicht anders.
Read the whole thing, absolutely.
Overwhelmingly, a government unconstrained by constant challenge is guaranteed to do far more damage, to enslave and outright murder far more people, than even the most wicked of outlaws.