I think they’ve implied it in dissenting views.

For most Americans SCOTUS’ opinions are just headlines. Staying silent except to speak through something that a majority of Americans don’t read or understand serves to further erode the court’s credibility

Out of sheer curiosity, is there any rules against a justice to secretly record audio of what the other justices are saying behind closed doors and leaking it to the press? In other words, if we crumble to a dictatorship, what would ketanji say she wished she had done besides a strong dessent?