A judge shall not testify as a character witness in a judicial, administrative, or other adjudicatory proceeding or otherwise vouch for the character of a person in a legal proceeding, except when duly summoned.
Ill. Sup. Ct. R. 3.3
COMMENTS
[1] A judge who, without being subpoenaed, testifies as a character witness abuses the prestige of judicial office to advance the interests of another. See Rule 1.3. Nothing in this Rule will affect or prohibit a judge's ability to provide a letter of recommendation on judicial letterhead for an individual based upon the judge's personal knowledge. See Rule 1.3, Comment [2].