If a witness’s probity is unknown, he is to be asked about. If the judge knows of his probity, he acts upon it. If the opposing party impugns the witnesses, he is required to produce evidence for it and, if he requests it, is granted three days. The claimant may keep him under restraint; if he does not produce evidence, judgment is rendered against him. If the judge does not know the standing of the witnesses, he asks the claimant to have them declared trustworthy. …………

His statement, “If a witness’s probity is unknown, he is to be asked about; if the judge knows of his probity, he acts upon it”: Witnesses fall into three categories before the judge:

The first is where the probity of the witnesses is unknown. This is what the author indicates by his words, “If a witness’s probity is unknown, he is to be asked about.” If the witnesses’ probity is unknown, the judge may neither rule on the basis of their testimony nor reject it. What, then, should he do? He should inquire and investigate. The jurists—may Allah have mercy on them—have mentioned that the judge should appoint people to inquire into the condition of witnesses; that is, he should establish a committee whose task and concern is to investigate the standing of witnesses, so that judgment may be easier and swifter. In our time, this does not exist, but a judge can, through his own means, inquire into the standing of witnesses when their probity is unknown.

The second is where their probity is known. The author says, “If the judge knows of his probity, he acts upon it.” He does not need a declaration of trustworthiness. Thus, it is pointless for two men, whose probity the judge knows, to testify, and then for it to be said: “So-and-so and so-and-so testified to such-and-such, and so-and-so and so-and-so declared them trustworthy.” The ones declaring them trustworthy may, in the judge’s view, be more ignorant, more unjust, and more sinful than the two witnesses themselves. But this has become a procedural practice.

The third is where the judge knows that a witness is flagrantly sinful. In that case, he does not act upon his testimony; rather, he rejects it. There is no need to request witnesses to establish the ground for impugning him, since the judge knows of his sinfulness. If it is asked: What is the ruling on the testimony of those who smoke tobacco?

According to the school, their testimony is rejected. According to the second view—namely, that the criterion is what people deem acceptable—their testimony is accepted if the opposing party considers them acceptable.