Which is why the threshold of evidence must be extremely high for death penalty convictions.

I am not of the belief that we should convict based upon a person's say so alone. Too many times, innocent people have been smeared or worse because someone decided to lie. Perjury should earn the same fate as the case they were lying about. The lack of punishment for perjury has led to many innocent people being convicted. If you can't prove a crime with physical/digital evidence, there is no crime.