07/19/2013 05:11 pm ET Updated Sep 18, 2013

Trayvon Martin and the Soul of a Prosecutor

The Trayvon Martin news cycle is now winding down. The marchers have quieted, the headlines have begun to fade, and inevitably there will emerge a different extraordinary story about race and violence in America. Still, among the many lessons we should draw from the Martin case is one about those who were involved in the litigation itself.

My vocation has been devoted to criminal law, first as a federal prosecutor and now as a professor, and there is only one absolute in my field: It is all tragedy. Every single case, every bit of it, is all tragedy. When we win a case as prosecutors, it does not un-murder a man or un-rape a woman. The best we can hope for (and it is at times a faint hope) is that we can prevent some future crime by that man.

To do the job of prosecution right, one cannot turn away from that raw, naked tragedy. You have to see, with open eyes, the harm that was done to victims, and the fact that there are victims to any crime worth pursuing. You have to acknowledge the humanity of the defendant and the pain that incarceration will cause not only to him, but to the family and others who depend on him. If you do this, if you do it right, it is emotionally draining. Constant tragedy exacts a price on the soul.

We rarely pause to consider it, either, this cost to people who are necessary to make our justice system work. Jurors, for example: We pay people $40 a day in capital cases to look a man in the eye and decide if he will live or die, a decision they will carry with them like lead in their pocket for the rest of their lives.

The Martin case must have been particularly difficult, because the evidence was fleeting and hard to accumulate (there were no objective eyewitnesses) and the politics of it never stopped swirling overhead. In the end, the prosecutors lost and faced that humbling moment where the defense attorney went on television to berate the decision to even charge the defendant.

Within my own faith, Christianity, we have a striking example of a frustrated prosecutor. Caiaphas, Christ's prosecutor, was faced with the dilemma of conflicting witnesses. He sent a servant girl out to find a true eyewitness to Jesus's claims, but she only comes across Peter, who denies three times that he knows the defendant. In the end, in his frustration, Caiaphas rips his shirt and simply cries out for crucifixion.

There is a Caiaphas moment for most prosecutors, where the burden of the job is overwhelming. Society has given you the job of taking away the freedom of fellow citizens, while arming those defendants with bold rights like the ability not to testify under the Fifth Amendment.

The soul of a prosecutor is tested in the moments like those the Zimmerman prosecutors face now. One reaction, too often, is that these public servants shut down their emotional engagement with the people they charge. They stop seeing them as people, and begin to see numbers, statistics, months in prison on a grid. Weariness strips the humanity from their work. The same process of emotional withering, of course, can occur with their equals in the public defender's office.

A loss seems huge when your job is to select those whose freedom should be deprived, or even whose lives should end. I know that feeling; I lost my very first case as a prosecutor. A more seasoned veteran told me something then that I have well remembered. Seeing how bad I felt, she opined that "Every loss is a grant of mercy, even if it is not justice."

That stayed with me. Many disagree with the verdict George Zimmerman received, but the case began a worthwhile discussion in our nation on "stand your ground" laws, and in the end mercy (which is different than justice) can be seen in the result. Few people feel the sting of that verdict as sharply as the prosecutors, but hopefully their souls will not harden and their eyes close to the tragedy embedded in every case, because that quiet change is one that takes the heart out of our system of justice.