Just copy blind auditions orchestras do.
Everything is done by typed text, with no humans visible. Jurors just sit isolated in a booth reading the text, or have the same person read out all the text to them.
Lawyers would be against it, but everyone would benefit from a society that decides guilt based on how convincing an argument is and not how convincing the person saying the argument is.
"Look at that man, he is guilty." Is not very convincing when the person who is supposedly guilty has never been seen.