Big problems with your last sentence..."know" someone is guilty is no excuse for falsely going to court to prove without sufficient evidence..
Prosecutors "knowing" has changed my opinion on the death penalty...too many prosecutors "knowing" put innocent men in jail...It can be a stepping stone to higher office for some of these scum bags......
Quite true.
However, in probably most cases of this type the guy may be innocent of the particular crime with which he is charged, but is not an “innocent person” in the usual sense of the term. He is probably a career criminal.
There is an element of poetic justice in a guy who commits hundreds of crimes and gets away with it being locked up for something he didn’t do.