Troy Davis may or may not be dead as I write. He was convicted of capital murder in Georgia (where Furman v. Georgia arose, invalidating the death penalty when Spot was just a pup, or a legal pup, anyway) on the basis of mostly recanted eyewitness testimony.
Have you even gone to a party -- or any other gathering, for that matter -- and introduced yourself to the same person twice? I'll bet you have.
Or seen someone in a place where you aren't used to seeing him or her, and being unable to come up with a name? I'll bet you've done that, too.
Cognition and recollection are uncertain things; all human endeavor is fraught with error.
It takes a lot of hubris to put a man to death under the circumstances presented in the Davis case. Circumstances that will, I hope, haunt the Davis death merchants for the rest of their days.