עַל־פִּ֨י הַתּוֹרָ֜ה אֲשֶׁ֣ר יוֹר֗וּךָ וְעַל־הַמִּשְׁפָּ֛ט אֲשֶׁר־יֹאמְר֥וּ לְךָ֖ תַּעֲשֶׂ֑ה לֹ֣א תָס֗וּר מִן־הַדָּבָ֛ר אֲשֶׁר־יַגִּ֥ידֽוּ לְךָ֖ יָמִ֥ין וּשְׂמֹֽאל׃
You shall act in accordance with the instructions given you and the ruling handed down to you; you must not deviate from the verdict that they announce to you either to the right or to the left.
Torah Temimah points to Sanhedrin / Sifrei.
ימין ושמאל. אפילו נראה בעיניך על ימין שהוא שמאל ועל שמאל שהוא ימין.
English: Right and left — even if it appears in your eyes that right is left and left is right.
Reinforcement of the absolute character of the duty of obedience.
Derash on the verse (Sifrei) — not a formal named middah of the 13.
Personal perception that the court has reversed right and left does not authorize deviation from its ruling.