I mean pretty much that's a cornerstone of our legal system. There's a strong bias against hidden courts where someone may be convicted in secret and punished in secret.
I would say that we want to know what crimes our government is convicting people of. Otherwise, you can have the government arrest and convict some one of "secret" charges, perhaps in "secret" courts with "secret" evidence. The convicted just disappeared.
I think we had something like that happen before, it caused a bit of upset.