Radak, Malbim: It is about judges who judge improperly. Perhaps it was composed in the days of Yehoshafat, for we see that when he returned from Ramos Gil'ad and returned Yisrael in Teshuvah, he established judges in all cities of Yehudah and warned them greatly - "Lo l'Adam Tishpetu Ki la'Shem...", "Yehi Pachad Hashem Aleichem... Ein Im Hashem Elokeinu Avlah u'Maso Fanim u'Mikach Shochad" (Divrei ha'Yamim II, 19:6-7). It seems that before this, the judges were corrupt, and he needed to establish different judges and warn them greatly about Mishpat.

Avos 3:6: If 10 sit and engage in Torah, the Shechinah is among them.

Brachos 6a #1: Ha'Kadosh Baruch Hu is found in the Beis ha'Keneses.

Brachos 6a #2: When 10 pray, the Shechinah is among them.

Sanhedrin 6b: The judges should know in front of Whom they judge, and Who will pay up from them (if they judge improperly).

Sanhedrin 7a: Any judge who judges properly, He causes the Shechinah to dwell in Yisrael; one who judges improperly, He causes the Shechinah to depart.

Rashi: He stands among the judges, to see if they will judge truthfully.

Radak: His honor is with you to oversee your deeds. This is like "Rak Eschem Yadati mi'Kol Mishpechos ha'Adamah Al Ken Efkod Aleichem Es Kol Avonoseichem" (Amos 3:2).

Malbim: Hashem stands among the litigants and witnesses, who need to stand.

Avos 3:6: If three sit and engage in Torah, the Shechinah is among them.

Brachos 6a: If three sit and engage in judgment, the Shechinah is among them.

Sotah 47b: When those who whisper to judges [to try to persuade them to favor one side] increased, Hashem's anger against Yisrael increased, and the Divine Presence departed.

Radak: Hashem stands among the judges, that they will judge straightly, like He commanded. If not, He will know and punish them.

Malbim: Hashem is among the judges and judges with them. The verse depicts that Hashem is inside the judges' hearts; He warns them and tells them... (refer to 82:2:1:1).