It's a common idiom in the English language: http://www.usingenglish.com/reference/idioms/judge,+jury+and...

My point is exactly that they are convicted and sentenced by the court system, not the public. For this reason the public have no need to learn their names in very prejudicial cases.

That said, this would have to be very strictly applied as it does interact problematically with the first amendment. As I said, I'm not sure this specific case warrants it.