With DNA testing foolproof you have almost a 100% chance of getting it right where blood or skin samples have been retrieved from a perp.
Of course not all cases involve perp DNA. And many cases there are no witnesses.
It’s a crap shoot. But fast execution (a year at most...not decades) is need at this time to make execution a deterant.
I am absolutely for the death penalty, when there is physical evidence tying the suspect to the crime.
Without physical evidence, however, we can have a case like that of Tim Masters, who was falsely imprisoned after a kangaroo trial where the prosecutors used weak circumstantial evidence to fabricate a case against him. No murder weapon was found, no blood was found anywhere on his clothes or in his house, there was nothing to tie him to the crime at all. He was imprisoned for 10 years. He has since sued for wrongful imprisonment and received $10 million for it. It’s a shame the taxpayers have to foot the bill for that—as much as possible of that should be taken from the prosecutors who railroaded him.