Masechet Makkot, Perek Alef (Chapter One), Mishnah Dalet will now talk about how the edim (witnesses) become zomemim, become people who we discredit and say that their testimony was not true, and then in turn receive the punishment they were trying to plot for somebody else. The Mishnah says, “Ein ha-edim na'asin zomemim ad sheyazimu et atzman.” Witnesses do not become zomemim unless other witnesses discredit them personally.
In other words, a second pair of witnesses challenges the first pair and tells them that they were in another place when they claim to have seen a certain aveira (transgression) take place. But if the second pair of witnesses shows up and just contradicts the testimony about the person who was killed, for example, then the first set of witnesses is not zomemim. We'll elaborate. We'll explain what we mean. How does this apply? If witnesses show up to Beit Din (rabbinical court) and say, “We saw Peloni (a certain man) kill someone in a certain place on a certain day,” and then other witnesses show up and say, “How could you testify that this event occurred at this time on this day? The person who was killed, or the person you claimed was the killer, was with us on the day and at the time you spoke about, and we were in a different location,” then the murder you claimed happened cannot have happened as you claimed. In this case, ein elu zomemim. The first witnesses are not considered to be edim zomemim. The second witnesses just contradicted their testimony, but there's no reason to believe one over the other. And they're not claiming anything about the witnesses themselves. They're claiming something about the case. They're arguing about what actually happened. But that's not an example of edim zomemim.
But the following is an example of edim zomemim, where the second witnesses discredit the first witnesses personally. If the second witnesses said to the first witnesses, “How could you testify that a murder occurred? You don't have the credibility to testify about that murder.” Why? “Because you were with us on that day that you're claiming a murder happened in such and such a place.” So therefore, you have no claim that you saw an actual murder in this case. The second witnesses are not testifying about the case, about the murder; they're not saying anything about the murder. Rather, what are they saying? That the first witnesses could not possibly have seen anything because they were with these two witnesses in a different location during that time. Harei elu zomemim. In this case, the first witnesses are edim zomemim, and they're finished with what they planned to do to the person they were testifying about. They tried to cause that person to be executed in our example. So therefore, they would also be liable for murder and to be put to death. Vehen neheragin al pihem. They put to death on the basis of the testimony of the second witnesses.