Roger Coleman, who was the subject of the book I recommended a year ago, has been proven guilty by DNA testing (story here). Had the test come out the other way, it would have galvanized the movement against the death penalty. As it stands, it's lending support to the types of people who have already left comments on my previous entry this morning.
Has this changed my opinion about the death penalty? No. I still think it's barbaric and antiquated. I still think the disparate effects based on race and socioeconomics are unjustifiable. And while it remains to be proven that an innocent person has been executed, plenty of innocent people have been sentenced to death and subsequently exonerated. The fact that Coleman was guilty doesn't mean that everyone else was, and more posthumous DNA testing will eventually reveal an innocent victim of capital punishment.
As for the book, I said initially that May God Have Mercy is not an anti-death penalty treatise. It's a story about individuals, and stories about individuals are ineffective when it comes to arguing the death penalty issue. As the new comments point out, people are already seeing this single case as a (pardon the term) death blow to the entire movement against capital punishment. Similarly, a "Save Tookie!" sign isn't nearly as effective as an "End the Death Penalty Sign," since the former simply enables the other side to accuse you of putting the rights of killers above the rights of victims.
The issue with respect to capital punishment isn't whether you want a particular individual to die. The question is whether you're comfortable with the danger of innocent people being sentenced to death, with the hypertechnical and ineffective appellate process, with the undeniable racial and socioeconomic disparities in the capital punishment system, and, ultimately, with the idea of the government killing in cold blood. It's these issues, not the Roger Colemans of the world, that will ultimately decide the death penalty question.