Rashi on Exodus 23:1/רש"י על שמות כ״ג:א׳

1לא תשא שמע שוא THOU SHALT NOT HEAR A FALSE REPORT — Take it as the Targum renders it: thou shalt not accept (listen to) a false report. This is a prohibition addressed to one who is about to accept a slanderous statement, and it is addressed also to a judge — that he should not hear the pleadings of one party to a suit before the other appears (Mekhilta; Sanhedrin 7b).

2אל תשת ידך עם רשע SET NOT THINE HAND WITH THE WICKED — with him who makes a false claim against his fellow-man: that you promise him to give evidence for him that will result in wrong being done (להיות עד חמס).‎