If it wasn’t for one tragic evening, we may never have known his name. The all too familiar dry pops from a pistol. A family left to grieve in the aftermath. A suspect arrested days later, charged with capital murder. The victim was a police officer, Mark MacPhail, working part-time as a security guard to provide for his wife and two young children. The conviction was a cakewalk for prosecutors, the sentence swift.

For 20 years, Troy Davis said they had the wrong man. That despite eyewitness testimony, he did not pull the trigger. The case worked and re-worked its way through the courts, from bench to bench, gaining momentum as world leaders, including two former U.S. presidents — Carter and Clinton — and a FBI director, began to express doubts about the once rock-solid case. Twenty-seven former prosecutors, a former Georgia congressman and a Bush administration deputy attorney General also from Georgia — all staunch death penalty advocates — urged the courts to halt the execution and re-open the case.

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Despite the ground swell of support from dignitaries, celebrities and millions of people from around the globe, despite the unraveling eyewitness testimony and lack of physical evidence, Troy Davis was executed at the Georgia Diagnostic and Classification Prison at Jackson, Georgia. The five-member Georgia State Board of Pardons and Parole refused to spare his life. Neither Governor Deal nor President Obama had the constitutional power to intercede.

The MacPhail family said, for them, the legal process was filled with frustration and agony. Convinced Davis had indeed murdered the military veteran and family man, they just wanted it to be over.

So on September 21, just after 11 p.m. Troy Davis was allowed to give a final statement and given a lethal injection.

And that might have been the end of the story.

But there was something about that powder blue casket. Something about that choir, clothed in black and singing songs of praise. There was something about the photos that flanked his body on the altar — one as a young boy and the other as a young man suited for his murder trial. Something about the thousand or so who gathered at Jonesville Baptist Church and the thousands of others who joined online. There was something, something about that preacher’s voice, the one who pastors Ebenezer Baptist where Dr. King once did. But more than that, there was something about Troy’s last words spoken in the death chamber surrounded by those who had come to watch him die. He said he was sorry for the family of officer MacPhail, but that he was innocent.

“I’d like to address the MacPhail family,” Davis, who declined his last meal, said. “Let you know, despite the situation you are in, I’m not the one who personally killed your son, your father, your brother. I am innocent.”

He was calm, according to witnesses, as he said, “The incident that happened that night is not my fault. I did not have a gun.”

The little brown boy who grew up on the streets of Savannah’s Cloverdale neighborhood left this world as regarded as a cold-blooded cop killer by some and a symbol of injustice for many others.

If we let the chapter end with Troy, we will never know. And that would suit some just fine. I am not one of those people.

My own father was murdered in 1973. My brother was assassinated in a drug turf war in the early 1990s. I have believed in the death penalty my entire life, an advocate, I believed, for the ultimate justice.

“An eye for an eye,” my faith tells me. But there was something about Troy, something about Todd Willingham who was killed after being convicted of murdering his children in Corsicana, Texas, and something about Georgia Stinney, Jr. who was just 14 years old when he was executed in Jim Crow-era South Carolina that gives me pause.

There is no appealing death. When we are wrong there is no turning back. When we are wrong, no matter how well intentioned, it makes murderers of us all. Because of Troy, I now understand just how wrong we’ve been and potentially often. That’s not the kind of justice that serves us. But for the ability to afford effective counsel, almost any one of us could find ourselves in Willingham or Davis’ shoes. That alone should keep you awake at night.

It would be easy to forget them all, easy to move on with our lives. After all, it wasn’t you or me on that gurney. But Troy won’t let us.

“Everything we do today will clear the way for a better tomorrow,” he said in a pre-recorded message played at the close of his memorial service. “We can correct all the wrongs if we band together. Don’t give up the fight.”