“We testify against so-and-so that he is liable to forty lashes,” and they were found to be zomemim, they are flogged eighty [lashes] —- because of (Exodus 20:13): You shall not bear false witness against your neighbor, and because of (Deut. 19:19): And you shall do to him as he planned to do; [these are] the words of R' Meir. But the Sages say: They are flogged only forty [lashes]. They divide [payments of] money, but they do not divide lashes. How so? [If] they testified against him that he owed another two hundred zuz, and they were found to be zomemim, they divide [it] among themselves. But if they testified against him that he was liable to forty lashes, and they were found to be zomemim, each one is flogged forty [lashes].

The witnesses do not become zomemim unless they discredit them personally. How so? [If] they said, “We testify against so-and-so that he killed someone”; [and others] said to them, “How can you testify [so], when this murder victim,” or “this murderer,” “was with us on that day in such and such a place” —- these are not [considered] zomemim. But [if] they said to them, “How can you testify [so], when you were with us on that day in such and such a place,” these are [considered] zomemim, and they are executed by their testimony.