Chazaka meikara mevarer

23. The testimony of one who is biblically disqualified is void even if they did not make a formal proclamation in the synagogues and study halls. If one who is rabbinically disqualified testified before a formal announcement, the testimony is valid. Even a biblical disqualification should only be used in a case where we are certain, but not in a case of doubt, such as where he testified in court and witnesses subsequently came and testified that he violated a sin that would biblically disqualify him but we are unsure whether he violated it before his testimony or after. In such a case, we keep the individual in his original status and anything that he testified on is valid until we know that he violated the sin before his testimony. If an individual required a formal announcement for a rabbinical disqualification and he received a public punishment for the sin, such as his removal from the synagogue, it is as if they made a formal announcement.

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And these on the following list are the ones who are disqualified by the Sages from bearing witness due to their unseemly behavior, as they are considered wicked individuals guilty of monetary transgressions: One who plays with dice [bekubbiyya] for money, and one who lends money with interest, and those who fly pigeons, and merchants who trade in the produce of the Sabbatical Year, which may be eaten but may not be sold as an object of commerce. Rabbi Shimon said: Initially, people would call them: Gatherers of the produce of the Sabbatical Year. Once the tax collectors grew abundant they would then call them: Merchants who trade in the produce of the Sabbatical Year, as the Gemara will explain. Rabbi Yehuda said: When are the people listed above disqualified from bearing witness? It is when they have no occupation but this one. But if they have an occupation other than this one, although they also make money by these inappropriate means, they are fit to bear witness.

§ The mishna teaches that Rabbi Yehuda says: When are all these people, e.g., gamblers and those who lend with interest, disqualified from bearing witness? It is when they have no occupation other than this one. Rabbi Abbahu says that Rabbi Elazar says: The halakha is in accordance with the opinion of Rabbi Yehuda.

And Rabbi Abbahu says that Rabbi Elazar says: All of these require a proclamation in the court. In other words, one is disqualified only after it is proclaimed in court that he was found guilty of this behavior.