Siman 23כ״ג
1 א

עד מתי נאמן הדיין לומר לזה זכיתי. ובו סעיף אחר:
כל זמן שבעלי דינים עומדים לפני הדיין נאמן לומר לזה חייבתי ולזה זכיתי נסתלקו מלפניו אינו נאמן ואם אין בידו פסק דין ודוקא בשודא דדייני אבל דין התלוי בטענות לא שייך בו נאמנות שלפי הטענות יזכה הזוכה ובלבד שלא יסתור טענות הראשונות וכל זה דוקא בדיין א' אבל שנים נאמנים לעולם ואפי' אם יש ב' עדים שמכחישים אותם: הגה וה"ה אם קבלו עליהם פשרן לזמן כל מה שאומר תוך זמן נאמן אבל אם כבר כתב ונתן להם הפשרה אין לו רשות להוסיף או לגרוע (אפי' תוך הזמן) אע"פ שאומר שכך היתה כוונתו (ב"י בשם רשב"א):

As long as the litigants are [still] standing before the Judge, he is believed when he states, 'I have pronounced this party guilty' and 'I have pronounced that party not guilty.' [As soon as] they are dismissed from his presence, he is not believed.1Kid. 74a: ‘A Judge is believed when he states, I have pronounced this one not guilty; I have pronounced that one guilty. When does this apply? Only if the litigants are (still) standing before him; but if they no longer stand before him, he is not believed. But let us see who holds (the document containing) the verdict in favour (since they gave a written verdict to each litigant)? — It refers to a case where the written document was torn. Then let us give them a re-trial? — (It refers to a case of) discretionary judgment (i.e., the Judge based his verdict on discretion and could not decide on the basis of any law. In this case we cannot be certain that a re-trial will result in the same decision).’ , Ket. 85b. An arbitrator is likewise not believed when he states that the settlement was according to such and such terms if the litigants are no longer before him (RaShBA) — M.E. , Isserles anon. This is based on the following case cited by B.Yos. supra § 12: A gave B a gift of bonds and took an oath that he will not collect any of the debts covered by the bonds. Subsequently A and B were in dispute concerning other claims and they accepted an arbitrator on condition that whatever settlement he reaches within a certain time limit should be effective and the latter arbitrated the case and ruled that A and B should remit their claims by means of a written document excluding the case of the bonds that A had made a gift to B which are to remain in effect as of the day of arbitration and later it was discovered that A had collected money on the strength of the bonds given to B and the latter contends that the money collected by A should be returned, to which A responds that since he collected the money prior to the date on which the document of remittal became effective, notwithstanding the fact that he presented the bonds to B on condition that they remain in their original force, he should be exempt from returning the collected money especially since it states in the document of remittal drawn up by the arbitrator that the settlement excludes the bonds as of the date of arbitration. The arbitrator was consulted and he agreed with A. Responsum: The law accords with B’s claim because when the other claims between A and B were submitted to the arbitrator, it was unknown that A had collected money on the strength of the bonds, for it was presumed that the bonds were intact since A took an oath to this effect. Consequently this did not enter into the remittal. And as to the statement of the arbitrator, he is not believed because he did not make this declaration when the litigants were still before him as in the present ruling with regards to a Judge. Nethiboth writes that the Judge is believed as long as the litigants still stand before him even if the one who was pronounced guilty could employ the principle of Miggo (i.e., since the the litigant could have stated ‘I did not accept you as Judge’), because since the Judge is believed as two witnesses, it would be tantamount to a Miggo in face of witnesses which is not effective. If the litigant contends that the Judge had pronounced judgment in his favour but the Judge and the other litigant state that the verdict had not yet been given, the Judge is believed even where the litigants are no longer before him provided that there are witnesses who testify that the litigants accepted him as Judge; but if there are no witnesses available and the litigants are no longer before the Judge, the claim of the litigant is accepted on the principle of Miggo, viz., that they did not accept him as Judge. And in this case the principle of Miggo in the face of witnesses (i.e., if we accept the statement of the Judge as equivalent to the testimony of two witnesses) is not accepted since the litigants are no longer before the Judge, in which case the latter is not regarded as equivalent to two witnesses — Nethiboth. However, the Judge is believed as one witness, provided he is not a relative or an otherwise ineligible person, and hence places the litigant who contradicts him under an oath and exempts the one who supports his statement from taking an oath. If the Judge died or left and the litigants contradict each other, each one stating that judgment was pronounced in his favour, — the law is that if one is the possessor (מוחזק) of the disputed article, the onus rests on the other party to produce evidence in order to substantiate his claim; if both are possessors, they divide the disputed article; if both are not possessors, the stronger of the two obtains possession or they make a settlement — M.E. And [this refers to a case] where the written verdict is not in his [the litigant's] possession,2Kid. ibid. , previous note beg. This means that if the litigant has the judgment writ, the Judge is believed even if they are no longer standing before him. Accordingly, the question in the Gemara ibid., ‘Let us see who holds (the document containing) the verdict in favour’ refers to the latter part of the cited Baraitha (i.e., ‘but if they no longer stand before him, he is not believed’). RITBA, however, refers this question to the first part of the Baraitha (i.e., ‘the Judge is believed only if the litigants are still standing before him’). In other words, why rely on the Judge if we can see the judgment writ. For if it refers to the latter part of the Baraitha, the following difficulty arises: If we do not believe the Judge, why accept the judgment writ? — ShaK. Where the judgment writ held by A contains an undefined statement, e.g., ‘The land of So-and-so belongs to you,’ and B claims that the judgment writ was in his possession but he lost it, then the Judge is believed when he says, ‘I ruled in favour of this party’ — ShaK. and [this ruling is applicable] only to a case of discretionary judgment;3Kid. ibid. , supra n. According to R. Tam (Kid. ibid., Tosaf. s.v. שודא a.e.) discretionary judgment means favouring or making a gift to any one of the litigants. Rashi: The Judges use their discretion in order to determine which of the claimants is to be believed. However, even if the litigants accepted the Judge to give a verdict based on discretionary judgment, it is still doubtful whether a re-trial would result in the same verdict — ShaK, Nethiboth. but in [the case of] a verdict which depends upon the pleas [of the litigants], reliance [on the Judge] does not apply, for in accordance with [the restatement of] the pleas the one who deserves favourable judgment will be so pronounced4And even while the litigants are still before the Judge, the latter is not believed, but he must clarify the matter by stating, ‘So-and-so, you have pleaded thus and So-and-so, you have pleaded thus and accordingly, You are not guilty and You are guilty’ — M.E., ShaK a.o. provided he [the litigant] does not upset his former pleas.5e., there is a controversy between them, viz., the Judge says, You pleaded thus, and the litigants contradict him, in which case the Judge is not believed when they are no longer before him (and according to ShaK even if they are still before him) — M.E. This entire [ruling applies] only to one Judge;6E.g., an authoritative Judge (Mumḥeh) or where they accepted him as Judge (according to ShaK by means of Kinyan, but M.E. maintains that Kinyan is not necessary) — M.E. Thus Tur, Asheri and RIBaSh in Resp. but two [Judges] are always believed,7For then their statement is equivalent to evidence and they are believed — M.E. Even if it is not a case of discretionary judgment — Nethiboth. Cf. B.M. 32a; Tosef. B.M. I, 6. even if there are two witnesses who contradict them.8Asheri in Resp. advances the following reason: The Judge is more conscious of the case than those who merely hear the proceedings. If one Judge in conjunction with a single witness made this statement and two witnesses contradict them, the Judge and the single witness are not believed, since the single witness merely heard the proceedings. Consequently, there is only one against two — M.E. Gloss: So too, if they [the litigants] accepted an arbitrator [to bring about a settlement] within a certain time limit, — [the law is that with respect to] everything he [the arbitrator] states within the time limit, he is believed. However, if he had already recorded the settlement in writing and given [it] to them, he [subsequently] has no right to add or to subtract [therefrom] even within the time limit, although he states that thus was his [original] intention.9B.Yos. on the authority of RaShBAG. , supra n.