(טז) וַיֹּ֨אמֶר ה' אֶל־מֹשֶׁ֗ה אֶסְפָה־לִּ֞י שִׁבְעִ֣ים אִישׁ֮ מִזִּקְנֵ֣י יִשְׂרָאֵל֒ אֲשֶׁ֣ר יָדַ֔עְתָּ כִּי־הֵ֛ם זִקְנֵ֥י הָעָ֖ם וְשֹׁטְרָ֑יו וְלָקַחְתָּ֤ אֹתָם֙ אֶל־אֹ֣הֶל מוֹעֵ֔ד וְהִֽתְיַצְּב֥וּ שָׁ֖ם עִמָּֽךְ׃ (יז) וְיָרַדְתִּ֗י וְדִבַּרְתִּ֣י עִמְּךָ֮ שָׁם֒ וְאָצַלְתִּ֗י מִן־הָר֛וּחַ אֲשֶׁ֥ר עָלֶ֖יךָ וְשַׂמְתִּ֣י עֲלֵיהֶ֑ם וְנָשְׂא֤וּ אִתְּךָ֙ בְּמַשָּׂ֣א הָעָ֔ם וְלֹא־תִשָּׂ֥א אַתָּ֖ה לְבַדֶּֽךָ׃
(14) I cannot carry all this people by myself, for it is too much for me. (15) If You would deal thus with me, kill me rather, I beg You, and let me see no more of my wretchedness!” (16) Then ה' said to Moses, “Gather for Me seventy of Israel’s elders of whom you have experience as elders and officers of the people, and bring them to the Tent of Meeting and let them take their place there with you. (17) I will come down and speak with you there, and I will draw upon the spirit that is on you and put it upon them; they shall share the burden of the people with you, and you shall not bear it alone.
(ג) כַּמָּה בָּתֵּי דִּינִין קְבוּעִין יִהְיוּ בְּיִשְׂרָאֵל וְכַמָּה יִהְיֶה מִנְיָנָן. קוֹבְעִין בַּתְּחִלָּה בֵּית דִּין הַגָּדוֹל בַּמִּקְדָּשׁ. וְהוּא הַנִּקְרָא סַנְהֶדְרִי גְּדוֹלָה. וּמִנְיָנָם שִׁבְעִים וְאֶחָד. שֶׁנֶּאֱמַר (במדבר יא טז) "אֶסְפָה לִּי שִׁבְעִים אִישׁ מִזִּקְנֵי יִשְׂרָאֵל" וּמשֶׁה עַל גַּבֵּיהֶן שֶׁנֶּאֱמַר (במדבר יא טז) "וְהִתְיַצְּבוּ שָׁם עִמָּךְ" הֲרֵי שִׁבְעִים וְאֶחָד.
וְעוֹד מַעֲמִידִין שְׁנֵי בָּתֵּי דִּינִין שֶׁל עֶשְׂרִים וּשְׁלֹשָׁה עֶשְׂרִים וּשְׁלֹשָׁה אֶחָד עַל פֶּתַח הָעֲזָרָה וְאֶחָד עַל פֶּתַח הַר הַבַּיִת. וּמַעֲמִידִין בְּכָל עִיר וָעִיר מִיִּשְׂרָאֵל שֶׁיֵּשׁ בָּהּ מֵאָה וְעֶשְׂרִים אוֹ יוֹתֵר סַנְהֶדְרִי קְטַנָּה וְיוֹשֶׁבֶת בְּשַׁעַר הָעִיר שֶׁנֶּאֱמַר (עמוס ה טו) "וְהַצִּיגוּ בַשַּׁעַר מִשְׁפָּט". וְכַמָּה יִהְיֶה מִנְיָנָם עֶשְׂרִים וּשְׁלֹשָׁה דַּיָּנִים וְהַגָּדוֹל בְּחָכְמָה שֶׁבְּכֻלָּן רֹאשׁ עֲלֵיהֶן וְהַשְּׁאָר יוֹשְׁבִין בְּעִגּוּל כְּמוֹ חֲצִי גֹּרֶן כְּדֵי שֶׁיְּהֵא הָרֹאשׁ רוֹאֶה אֶת כֻּלָּן:
(ד) עִיר שֶׁאֵין בָּהּ מֵאָה וְעֶשְׂרִים מַעֲמִידִין בָּהּ שְׁלֹשָׁה דַּיָּנִים שֶׁאֵין בֵּית דִּין פָּחוֹת מִשְּׁלֹשָׁה כְּדֵי שֶׁיְּהֵא בָּהֶן רֹב וּמִעוּט אִם הָיְתָה בֵּינֵיהֶן מַחְלֹקֶת בְּדִין מִן הַדִּינִין:
(3) How many established courts should there be among the Jewish people and how many judges should there be in each court? First, a supreme court is established in the Temple. This is called the Great Sanhedrin. It was composed of 71 judges. This is derived from Numbers 11:16 which states: "Gather for Me seventy men from the elders of Israel." And Moses presided over them, as the verse continues: "And they shall stand there with you." Thus there are 71.
In addition, two courts of 23 judges each are appointed. One holds sessions at the entrance to the Temple courtyard. and the other at the entrance to the Temple Mount.
In addition, in every city in Israel in which their are 120 or more adult males, we appoint a minor Sanhedrin. They hold court at the entrance to the city, as implied by Amos 5:15: "And you shall present judgment in your gates." How many judges should be in such a court? 23. The one who possesses the greatest wisdom is the chief justice and the remainder sit in a semi-circle so that the chief justice can see all of them.
(4) When there are less than 120 adult males in a city, we appoint a court of three judges. For a court should never be less than three. In that way, there will be a majority and a minority if there is a difference of opinion in any particular judgment.
(ו) דִּינֵי מָמוֹנוֹת וְכֵן הַטֻּמְאוֹת וְהַטָּהֳרוֹת מַתְחִילִין מִן הַגָּדוֹל שֶׁבַּדַּיָּנִים וְשׁוֹמְעִין אֶת דְּבָרָיו. וְדִינֵי נְפָשׁוֹת מַתְחִילִין מִן הַצַּד וְאֵין שׁוֹמְעִין דִּבְרֵי הַגָּדוֹל אֶלָּא בָּאַחֲרוֹנָה:
(6) With regard to cases involving monetary matters and similarly questions of ritual purity and impurity, the judge of the greatest stature gives his ruling first and the other judges hear his ruling. With regard to laws involving capital punishment, we begin from the side. The words of the judge of the highest stature are not heard until the end.
https://www.rabbinicalassembly.org/jewish-law/committee-jewish-law-and-standards

