Halacha

הלכה א
עַד אֵימָתַי יוֹשְׁבִין הַדַּיָּנִים בְּדִין. סַנְהֶדְרִי קְטַנָּה וּבֵית דִּין שֶׁל שְׁלֹשָׁה יוֹשְׁבִין מֵאַחַר תְּפִלַּת הַשַּׁחַר עַד סוֹף שֵׁשׁ שָׁעוֹת בַּיּוֹם. אֲבָל בֵּית דִּין הַגָּדוֹל הָיוּ יוֹשְׁבִין מִתָּמִיד שֶׁל שַׁחַר עַד תָּמִיד שֶׁל בֵּין הָעַרְבַּיִם. וּבְשַׁבָּתוֹת וְיָמִים טוֹבִים הָיוּ יוֹשְׁבִין בְּבֵית הַמִּדְרָשׁ שֶׁבְּהַר הַבַּיִת:
כסף משנה
1.
Until when should the judges hold session? A minor Sanhedrin and a court of three should hold sessions from after the morning service until the end of the sixth hour of the day. The supreme Sanhedrin, by contrast, would hold sessions from the time of the slaughter of the morning sacrifice until the offering of the afternoon sacrifice. On Sabbaths and on festivals they would hold sessions in the House of Study on the Temple Mount.

הלכה ב
אֵין בֵּית דִּין שֶׁל שִׁבְעִים וְאֶחָד צְרִיכִין שֶׁיִּהְיוּ יוֹשְׁבִין כֻּלָּן כְּאֶחָד בִּמְקוֹמָן שֶׁבַּמִּקְדָּשׁ. אֶלָּא בְּעֵת שֶׁיְּהוּ צְרִיכִין לְהִתְקַבֵּץ מִתְקַבְּצִין כֻּלָּן. וּבִשְׁאָר הָעִתּוֹת כָּל מִי שֶׁהָיָה לוֹ עֵסֶק יֵצֵא לַעֲשׂוֹת חֶפְצוֹ וְחוֹזֵר וְהוּא שֶׁלֹּא יִפְחֲתוּ מֵעֶשְׂרִים וּשְׁלֹשָׁה יוֹשְׁבִין תָּמִיד כָּל זְמַן יְשִׁיבָתָן. הֻצְרַךְ אֶחָד מֵהֶן לָצֵאת הֲרֵי זֶה מִסְתַּכֵּל בַּחֲבֵרָיו הַנִּשְׁאָרִים אִם יִשָּׁאֲרוּ שָׁם עֶשְׂרִים וּשְׁלֹשָׁה יֵצֵא וְאִם לָאו לֹא יֵצֵא עַד שֶׁיָּבוֹא אַחֵר:
כסף משנה
2.
The High Court of 71 judges was not required to sit all together in their place in the Temple. Instead, when it was necessary for them to gather together, they would all gather together. At other times, whoever had private affairs would tend to his concerns and then return.
The above applies provided there would be no less than 23 judges in attendance whenever they were sitting. If a judge needs to leave, he should look at his colleagues who remain. If there are 23 remaining, he may leave. If not, he should not leave until another comes.

הלכה ג
אֵין מַתְחִילִין אֶת הַדִּינִין בַּלַּיְלָה. מִפִּי הַשְּׁמוּעָה לָמְדוּ שֶׁהַדִּינִין כִּנְגָעִים שֶׁנֶּאֱמַר (דברים כא ה) "כָּל רִיב וְכָל נָגַע" מָה רְאִיַּת נְגָעִים בַּיּוֹם בִּלְבַד אַף הַדִּינִין בַּיּוֹם בִּלְבַד:
כסף משנה
3.
A court should not begin adjudicating a case at night. According to the Oral Tradition, this concept was derived as follows: Based on Deuteronomy 21:5 which mentions: "Every dispute and every blemish," an equation is established between the adjudication of disputes and blemishes. Just as blemishes are viewed only during the day; so, too, disputes should be adjudicated only during the day.

הלכה ד
וְכֵן אֵין מְקַבְּלִין עֵדוּת וְאֵין מְקַיְּמִין שְׁטָרוֹת בַּלַּיְלָה. וּבְדִינֵי מָמוֹנוֹת אִם הִתְחִילוּ בַּיּוֹם מֻתָּר לִגְמֹר הַדִּין בַּלַּיְלָה:
כסף משנה
4.
Similarly, we do not listen to the testimony of witnesses or validate the authenticity of legal documents at night. With regard to cases involving monetary law, if the judges began hearing the matter during the day, it is permitted for them to conclude the judgment at night.

הלכה ה
הַנְּחָלוֹת כְּדִינִין שֶׁנֶּאֱמַר בָּהֶן לְחֻקַּת מִשְׁפָּט. לְפִיכָךְ אֵין מַפִּילִין נְחָלוֹת בַּלַּיְלָה:
כסף משנה
5.
The division of an inheritance resembles a judgment, for with regard to them, Numbers 35:29 states: "For the statutes of judgment." Therefore inheritances are not divided at night.

הלכה ו
שְׁנַיִם שֶׁנִּכְנְסוּ לְבַקֵּר אֶת הַחוֹלֶה וְצִוָּה בִּפְנֵיהֶם. כּוֹתְבִים וְאֵין עוֹשִׂים דִּין. וְאִם הָיוּ שְׁלֹשָׁה רָצוּ כּוֹתְבִין רָצוּ עוֹשִׂין דִּין. בַּמֶּה דְּבָרִים אֲמוּרִים בַּיּוֹם. אֲבָל בַּלַּיְלָה כּוֹתְבִין וְאֵין עוֹשִׂין דִּין:
כסף משנה
6.
When two people enter to visit a person who is deathly ill, if he makes statements dividing his estate in their presence, they may record his statements, but they may not adjudicate the division of the estate. They were three, if they desire, they may record his statements, or they may adjudicate the division of the estate.
When does the above apply? During the day. During the night, they may record his statements, but they may not adjudicate the division of the estate.

הלכה ז
כָּל בֵּית דִּין שֶׁל יִשְׂרָאֵל שֶׁהוּא הָגוּן שְׁכִינָה עִמָּהֶם. לְפִיכָךְ צְרִיכִין הַדַּיָּנִים לֵישֵׁב בְּאֵימָה וְיִרְאָה וַעֲטִיפָה וְכֹבֶד רֹאשׁ וְאָסוּר לְהָקֵל רֹאשׁ אוֹ לִשְׂחֹק אוֹ לְסַפֵּר בְּשִׂיחָה בְּטֵלָה בְּבֵית דִּין אֶלָּא בְּדִבְרֵי תּוֹרָה וְחָכְמָה:
כסף משנה
7.
Whenever a suitable court among the Jewish people sits in judgment, the Divine Presence rests among them. Accordingly, the judges must sit in awe and fear, wrapped in tallitot, and conduct themselves with reverence. It is forbidden to act frivolously, to joke, or to speak idle matters in court. Instead, one may speak only words of Torah and wisdom.

הלכה ח
כָּל סַנְהֶדְרִין אוֹ מֶלֶךְ אוֹ רֹאשׁ גּוֹלָה שֶׁהֶעֱמִידוּ לָהֶן לְיִשְׂרָאֵל דַּיָּן שֶׁאֵינוֹ הָגוּן וְאֵינוֹ חָכָם בְּחָכְמַת הַתּוֹרָה וְרָאוּי לִהְיוֹת דַּיָּן. אַף עַל פִּי שֶׁהוּא כֻּלּוֹ מַחֲמַדִּים וְיֵשׁ בּוֹ טוֹבוֹת אֲחֵרוֹת הֲרֵי זֶה שֶׁהֶעֱמִידוֹ עוֹבֵר בְּלֹא תַּעֲשֶׂה. שֶׁנֶּאֱמַר לֹא תַכִּירוּ פָנִים בַּמִּשְׁפָּט. מִפִּי הַשְּׁמוּעָה לָמְדוּ שֶׁזֶּה מְדַבֵּר כְּנֶגֶד הַמְמֻנֶּה לְהוֹשִׁיב דַּיָּנִין. אָמְרוּ חֲכָמִים שֶׁמָּא תֹּאמַר אִישׁ פְּלוֹנִי נָאֶה אוֹשִׁיבֶנּוּ דַּיָּן. אִישׁ פְּלוֹנִי גִּבּוֹר אוֹשִׁיבֶנּוּ דַּיָּן. אִישׁ פְּלוֹנִי קְרוֹבִי אוֹשִׁיבֶנּוּ דַּיָּן. אִישׁ פְּלוֹנִי יוֹדֵעַ בְּכָל לָשׁוֹן אוֹשִׁיבֶנּוּ דַּיָּן. נִמְצָא מְזַכֶּה אֶת הַחַיָּב וּמְחַיֵּב אֶת הַזַּכַּאי לֹא מִפְּנֵי שֶׁהוּא רָשָׁע אֶלָּא מִפְּנֵי שֶׁאֵינוֹ יוֹדֵעַ. לְכָךְ נֶאֱמַר (דברים א יז) "לֹא תַכִּירוּ פָנִים בַּמִּשְׁפָּט". וְעוֹד אָמְרוּ כָּל הַמַּעֲמִיד לְיִשְׂרָאֵל דַּיָּן שֶׁאֵינוֹ הָגוּן כְּאִלּוּ הֵקִים מַצֵּבָה שֶׁנֶּאֱמַר (דברים טז כב) "וְלֹא תָקִים לְךָ מַצֵּבָה אֲשֶׁר שָׂנֵא ה' אֱלֹהֶיךָ". וּבִמְקוֹם תַּלְמִידֵי חֲכָמִים כְּאִלּוּ נָטַע אֲשֵׁרָה שֶׁנֶּאֱמַר (דברים טז כא) "לֹא תִטַּע לְךָ אֲשֵׁרָה כָּל עֵץ אֵצֶל מִזְבַּח ה' אֱלֹהֶיךָ". וְכֵן אָמְרוּ חֲכָמִים (שמות כ כ) "לֹא תַעֲשׂוּן אִתִּי אֱלֹהֵי כֶסֶף" אֱלוֹהַּ הַבָּא בִּשְׁבִיל כֶּסֶף וְזָהָב זֶה הַדַּיָּן שֶׁמִּנּוּהוּ מִפְּנֵי עָשְׁרוֹ בִּלְבַד:
כסף משנה
8.
Whenever a Sanhedrin, a king, or an exilarch appoints a judge who is not fitting and/or is not learned in the wisdom of the Torah and is not suitable to be a judge - even if he is entirely a delight and possesses other positive qualities - the person who appoints him violates a negative commandment, as Deuteronomy 1:17 states: "Do not show favoritism in judgment." According to the Oral Tradition, we learned that this command is addressed to those who appoint judges.
Our Sages declare: "Perhaps a person will say: 'So and so is attractive, I will appoint him as a judge,' 'So and so is strong, I will appoint him as a judge,' 'So and so is my relative, I will appoint him as a judge,' or "So and so knows all the languages, I will appoint him as a judge.' This will lead to those who are liable being vindicated and those who should be vindicated held liable, not because the judge is wicked, but because he does not know Torah law. Therefore the Torah states: "Do not show favoritism in judgment."
Our Sages also declare: "Whoever appoints a judge who is not appropriate for the Jewish people is considered as if he erected a monument, as implied by Deuteronomy 16:22: "Do not erect a monument which is hated by God, your Lord." If he is appointed instead of a Torah scholar, it is as if one planted an asherah, as Ibid.:21 states: "Do not plant an asherah or any other tree next to God's altar."
And our Sages interpreted Exodus 20:20: "Do not make gods of silver and gods of gold together with Me" to mean "Do not appoint a judge because of silver and gold." This refers to a judge who was appointed because of his wealth alone.

הלכה ט
כָּל דַּיָּן שֶׁנָּתַן מָמוֹן כְּדֵי שֶׁיִּתְמַנֶּה אָסוּר לַעֲמֹד מִפָּנָיו. וְצִוּוּ חֲכָמִים לְהָקֵל אוֹתוֹ וּלְזַלְזֵל בּוֹ. וְאָמְרוּ חֲכָמִים שֶׁהַטַּלִּית שֶׁמִּתְעַטֵּף בָּהּ תְּהִי בְּעֵינֶיךָ כְּמִרְדַּעַת שֶׁל חֲמוֹר:
כסף משנה
9.
Whenever a judge pays money in order to be appointed, it is forbidden to stand in his presence. Our Sages commanded that he be denigrated and derided. And our Sages declare: "Consider the tallit with which he wraps himself as the saddle blanket of a donkey."

הלכה י
כָּךְ הָיָה דֶּרֶךְ חֲכָמִים הָרִאשׁוֹנִים בּוֹרְחִין מִלְּהִתְמַנּוֹת. וְדוֹחֲקִין עַצְמָן הַרְבֵּה שֶׁלֹּא יֵשְׁבוּ בַּדִּין עַד שֶׁיֵּדְעוּ שֶׁאֵין שָׁם רָאוּי כְּמוֹתָם וְשֶׁאִם יִמָּנְעוּ מִן הַדִּין תְּקַלְקֵל הַשּׁוּרָה. אַף עַל פִּי כֵן לֹא הָיוּ יוֹשְׁבִין בַּדִּין אֶלָּא עַד שֶׁמַּכְבִּידִין עֲלֵיהֶם אֶת הָעָם וְהַזְּקֵנִים וּפוֹצְרִים בָּהֶן:
כסף משנה
10.
This was the manner of conduct of the sages of the previous generations. They would flee from being appointed to a court and would undergo extreme pressure not to sit in judgment until they knew that there was no other person as appropriate as they were and that if they would refrain from participating in the judgment the quality of the legal system would be impaired. Even so, they would not sit in judgment until the people at large and the elders would compel them and implore them to do so.

שופטים הלכות סנהדרין והעונשין המסורין להם פרק ג
Shoftim Sanhedrin Chapter 3