The overwhelmingly majority of people placed on death row, and who have their executions carried out are, indeed guilty beyond a shadow of a doubt. The chance of a wrongful execution is extremely unlikely. In my view, the existence of bias or potential for mistakes in no way makes the death penalty “dangerous”, for no system is perfect. It’s impossible for anything to be perfect. But if a product has a 96% success rate, it is well within reason to use it accordingly.
I'm sorry, but saying that "the likelihood of innocent people getting executed is extremely low, but if it happens it is the price we must be willing to pay for keeping the death penalty" comes across as extremely cynical, callous and reckless. You seem to be more concerned with "properly" punishing murderers than to prevent involuntary manslaughter.