There needs to be an investigation into who leaked it. They might not ever find out who it was but if they can that person needs the most stringent punishment possible.
I'd start by looking at our newest Justice and her clerks/staff.
She's not a Justice yet so I don't know if she would have access. If she did though you are right that it would be a good place to start.
If it is found out who leaked it, he or she will be a hero to the left and that will be the end of our justice system. Or what’s left of it.