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.

[If] others came and they discredited them, [and still] others came, and they discredited them [too], even one hundred, all of them are executed. R' Yehudah says: This is a group of plotters, and only the first group is executed.

Zomemim witnesses are not executed unless the verdict has been delivered. For the Sadducees say: Unless he had been exe-cuted, as it is said: A life for a life. The Sages said to them: Has it not already stated (Deut. 19:21): And you shall do to him as he planned to do to his brother —- indicating that his brother is still alive! If so, why does it say, A life for a life? Because it might be thought that from the time their testimony is ac-cepted, they may be executed; [the Torah] therefore states: A life for a life —- [to teach] that they are not executed unless a verdict has been issued.

. By the testimony of two witnesses or three witnesses shall the one who is to die be put to death (Deut. 17:6). Now if the tes-timony may be established by two, why did Scripture specify by three? It is to compare three to two: Just as three can discredit two, so two can discredit three. How do we know that [this is true] even [for] one hundred? To teach [this] it states: witnesses. R' Shimon says: Just as two are not executed unless both are proved zomemim, so three are not executed unless the three of them are proved zomemim. How do we know that [this is true] even [for] one hundred? To teach [this] it states: witnesses. R' Akiva says: The third witness is mentioned only for the purpose of dealing stringently with him and to make his sen-tence the same as these. Now if Scripture punished one who joined transgressors like the transgressors [themselves], how much more will it reward the one who joins those who perform a mitzvah the same as those who perform the mitzvah!

Just as [with] two, [if] one of them is found [to be] a kinsman or a disqualified [witness], their testimony is void, so too [with] three, [if] one of them is found [to be] a kinsman or a disqualified [witness], their testimony is void. How do we know that [this is so] even [for] a hundred? To teach [this] it states: witnesses. Said R' Yose: In regard to what is this said? In regard to capital cases; but in regard to civil cases, the testimony is estab-lished through the remaining [witnesses]. Rabbi says: Both in civil cases and in capital cases, but only if they warned them. But if they did not warn them —- what should two brothers do who saw someone commit a murder?

[If] two saw him from this window, and two saw him from that window, and one in the middle warned him —- if some of them saw each other, then they are one set of witnesses; if not, they are two sets of witnesses. Therefore, if one of them is found to be zomemim, both he and they are executed, and the second [set] is exempt. R' Yose says: They are not executed unless his two witnesses warn him, as it is said (Deut. 17:6): By the testimony of two witnesses. Another explanation: By the testimony of two witnesses —- that a sanhedrin should not hear [testimony] from the mouth of an interpreter.

[If] one was sentenced and fled, and then came before that very same court, they do not overturn his sentence. Wherever two stand up and declare, “We testify concerning so-and-so that he was sentenced in so-and-so's court, and so-and-so and so-and-so were his witnesses,” he is executed. A sanhedrin functions both in the Holy Land and outside the Holy Land. A sanhedrin that executes once in a septenary is called a destroyer. R' Elazar ben Azariah says: Once in seventy years. R' Tarfon and R' Akiva say: Had we been on a san-hedrin, a person would never have been executed. Rabban Shimon ben Gamliel says: They too would have increased [the number of] murderers in Israel.

These are the ones who are exiled: One who kills a person inadvertently. [If] he was pushing out with a roller, and it fell upon him and killed him; [or if] he was letting down a cask, and it fell upon him and killed him; [or if] he was descending a ladder, and he fell upon him and killed him —- he is exiled. But if he was drawing back the roller, and it fell upon him and killed him; [or if] he was hoisting up the cask and the rope broke, and it fell upon him and killed him; [or if] he was ascending the ladder, and he fell upon him and killed him —- he is not exiled. This is the rule: For [any death which occurs] in the course of descent, he is exiled; but for [one which occurs] not in the course of descent, he is not exiled.  Should the iron fly off its handle and kill —- Rabbi says: He is not exiled; but the Sages say: He is exiled. From the tree that is being chopped —- Rabbi says: He is exiled; but the Sages say: He is not exiled.

[If] one throws a stone into a public domain and kills, he is exiled. R' Eliezer ben Yaakov says: If, after the stone left his hand, the other one put his head out and received the blow, he is exempt. [If] he threw a stone into his own yard and killed —- if the victim had a right to enter there, he is exiled, but if not, he is not exiled; as it is said (Deut. 19:5): And whoever comes with his fellowman into the forest —- [it must be] like the forest, which is a place into which [both] the victim and the assailant have permission to enter. This excludes the courtyard of the householder, into which the victim and the assailant may not [both] enter. Abba Shaul says: [It must be] like chopping wood, [which is] an optional act. This excludes the father who hits his son, and the teacher who chastises his pupil, and the agent of the court.

A father is exiled as a result of his son, and a son is exiled as a result of his father. All are exiled as a result of an Israelite, and Israelites are exiled as a result of them, with the exception of a resident alien. A resident alien is exiled only as a result of a resident alien.  A blind person is not exiled; [these are] the words of R' Yehudah. R' Meir [however] says: He is exiled.  An enemy is not exiled. R' Yose bar Yehudah says: An enemy is executed because he is considered forewarned. R' Shimon says: Some enemies are exiled and some enemies are not exiled. This is the rule: Anyone concerning whom it can be said [that] he killed intentionally is not exiled; but [if it is clear] that he killed unintentionally, he is exiled.