(6) A judge should not make public comment on the merits of a matter pending or impending in any court. A judge should require similar restraint by court personnel subject to the judge’s direction and control. The prohibition on public comment on the merits does not extend to public statements made in the course of the judge’s official duties, to explanations of court procedures, or to scholarly presentations made for purposes of legal education.
https://www.uscourts.gov/judges-judgeships/code-conduct-united-states-judges