Siman 20

One who was found liable by a beit din and afterwards found witnesses or evidence in his favor overturns the judgment and returns, and even if he already paid his litigant, they return and take it from him. And even if the beit din said to him at the time of the judgment, "Bring all the evidence you have within thirty days," and he brought it after thirty days, he overturns the judgment; for what could he have done if he did not find it within thirty days? Shall he lose his right because of this? But if when the beit din said to him, "Bring witnesses, bring evidence," and he said, "I have no witnesses and no evidence," and he found them afterwards, it is nothing. For presumably when he gave such an answer to the beit din, he examined thoroughly that he had no evidence or witnesses, and consequently one cannot rely on that which he brought afterwards, for certainly there is some forgery in this, as the admission of a litigant is like a hundred witnesses. But if without the questioning of the beit din he said, "I have no witnesses or evidence," he may bring them afterwards [Bach], for since he said it of his own accord without the questioning of the beit din, it is possible that he did not examine thoroughly and it only appeared to him as it seemed that he had none.

That which we have said, that when he answered the beit din "I have no witnesses or proof" and subsequently brought them it is nothing, nevertheless the witnesses are not disqualified for any matter in the world, even for this litigant himself. For even though we suspect him that there is some falsehood in this, nevertheless their falsehood has not been clarified, and it is a mere suspicion regarding this matter because he himself admitted that he has none [Urim VeTummim, and not like the Netivot HaMishpat]. But if when the beit din said to him "bring witnesses, bring proof" and he said "I have none," and they liable him, and when he saw that he was liable he said "let so-and-so and so-and-so approach and testify for me" and they testified, the matter is evident that they are false witnesses and there is a conspiracy between them. They are disqualified for any testimony of that man, and it is close to saying that they are disqualified for any testimony in the world [and so it appears from Rashi and the Nimukei Yosef, see there, section 31].

And if he did not answer the beit din, "I have no witnesses or proof," but rather remained silent when the beit din asked him, and afterwards, when they found him liable, he said, "Let so-and-so and so-and-so approach and testify for me," or he produced proof from his pocket—even though it appears somewhat that there is a concern of deception in this matter, in that he did not immediately answer the beit din, "I have witnesses or proof"—nevertheless, we accept the testimony and the proof. Since he did not answer, "I have none," and as for the fact that he remained silent, it is possible that he had some reason for the matter, and we do not have the power to disqualify the witnesses or the proof because of this. And so too regarding arguments: when the beit din asked him if he has further arguments and he remained silent, and they found him liable, and he subsequently argued arguments and contradicted the judgment, we accept the arguments from him and judge according to them, since he did not say, "I have no further arguments."

And that which we said in section 1, that if he answered the question of the beit din, "I have no witnesses or proof," he cannot bring them anymore, this is specifically regarding such witnesses and proofs that he should have known about, such as if they were in the city and the like, where it is clear that he knew of them. Therefore, since he said "I have none," it is obvious that there is no substance to them. But when witnesses and proof came to him from afar, or if his proofs were hidden in the hands of others who were not in the city and the like, and afterwards the people with whom the proofs were hidden arrived, he may bring them and overturn the judgment. This is because he can justify his words and say, "That which I said 'I have none' was because they were not available to me and I did not know of them." Therefore, if he specified and said at the time the beit din asked him, "I have no witnesses or proof, neither here nor in another place, neither with me nor with others," he can no longer bring them; for since he himself admitted that he has none in any place, certainly such is the truth, and that which he brought them afterwards, there is some collusion in this. And all this is specifically regarding one whose judgment was concerning his own affairs. But an heir who litigated in beit din concerning the affairs of his father or his other testators, and was a minor when his testator died, even though he is now an adult, and the heir said at the time the beit din asked him that he has no proof or witnesses, neither in this place nor in another place, and afterwards others came and said to him, "Know that there are proofs for your testator deposited with so-and-so," or witnesses who know of the affairs of your testator, behold, he may bring them and overturn the judgment. And even if the proofs and the witnesses were in the city, because a minor heir does not know all the proofs of his testators even if he grew up afterwards. And so too a purchaser regarding the proofs of the one who sold to him, when he needs them, it is possible that he did not know. But an heir who was an adult when his testator died, his law is like his own affairs, for he certainly investigated and inquired into all the affairs of his estate. And that which we said, that when he said "I have no witnesses or proof" and they came to him from another place that he may bring them, this is specifically when it is clarified that it is from another place, or that the beit din understands according to the matter that it was in another place and he did not know of them. But without this, we do not believe him. And so it appears that when he brings his proofs or the witnesses, the beit din must ask him, "Did you not say to us that you have no witnesses or proof?" If he answered, "I did not know of them," they accept them from him; and if he remained silent and did not answer, they do not accept them, for it is evident that they are not true [and so it appears from the words of the Bach, see there].

And all these matters apply in an ordinary case where it is not known to us whether he knew of the proofs or not; but if it was clarified that he did not know of the proofs or of the witnesses until now, he may bring them and overturn the judgment, even a great person in his own affairs and even if the proofs and the witnesses were in the city. And so too the opposite: a minor heir in the affairs of his testator—if it was clarified that he knew of these proofs at the time he went down to judgment, he can no longer bring them if he answered the beit din, "I have no witnesses or proof."