Earlier quoted context omitted.
The single rationale is perfectly fine. If we had a magic oracle which supplies us with the absolutely correct guilty or not guilty verdict, there would be no problem with the death penalty. > what does the death penalty actually achieve Rids the world of an instance of evil, efficiently and permanently. Vindicates victims.
You're reducing a human being to a single binary classification - evil or not evil - an assessment that ignores the circumstances of their life, mental state etc at a particular point in time. You're also saying that you're prepared to ignore the wider impact that the act of executing that individual has on society. On the apparent grounds that the dead victim is somehow vindicated (which I can only interpret as mean…
That is correct.
> You're also saying that you're prepared to ignore the wider impact that the act of executing that individual has on society.
That must specifically not be allowed to cloud our judgment. "Society" is word which refers to collection of people, the vast majority of whom have no connection to the case.