GEMARA

(Beraisa): If there is only one witness, he is exempt for Shevu'as ha'Edus;

R. Elazar b'Rebbi Shimon says, he is liable.

(Abaye): They agree that one witness about a Sotah is liable, if he saw that she sinned in seclusion, for the Torah believes him like two witnesses.

32b (Rav Papa): They agree that one witness that a man died (he is believed to permit the widow to remarry, and to collect her Kesuvah) is liable.

Makos 2a (Mishnah): If witnesses testify that a Kohen's mother was divorced or did Chalitzah (so he is a Chalal (Pasul Kohen)), we do not say that each witness becomes a Chalal. Rather, he is lashed.

(R. Yehoshua ben Levi): "Va'Asisem Lo Ka'asher Zamam" - to him, not to his descendants. (If the witness would become a Chalal, this would disqualify his descendants).

5a (Mishnah): If two witnesses testified that Ploni killed Shimon, and David and Moshe say 'how can you testify about this? That day, you were with us in a different place', the first witnesses are Zomemim. They are killed based on the testimony of David and Moshe.

If more witnesses testified, and they were Huzam, and more witnesses testified, and they were Huzam, all the Zomemim are killed.

R. Yehudah says, this is a conspiracy! Only the first pair is killed.

Bava Basra 56b (Mishnah): If David testified about three years of Chazakah, and three brothers testified, each about one of the three years, (this is testimony of Chazakah, for) testimony of each year is separate. It is like one testimony for Hazamah (they are exempt unless all of them are Huzmu).

Sanhedrin 78a (Rava): If witnesses testified about a Treifah and they were Huzmu, they are exempt. If Treifah witnesses were Huzmu, they are killed.

Rebuttal (Rav Ashi): Also Treifah witnesses who were Huzmu are not killed, for the testimony of the Mezimim (who said that the witnesses were elsewhere) cannot be Huzam (we could not kill them for trying to kill Treifos).

RISHONIM

Rambam (Hilchos Edus 20:8): If witnesses testified to convict a Rasha who is not lashed and does not pay money, and they were Huzam, they are lashed. E.g., they testified that a Kohen is a Ben Gerushah, or that Ploni killed b'Shogeg, or that his ox gored, or that he was sold to be an Eved Ivri. A tradition from Sinai teaches that they are lashed.

Rambam (21:4): If witnesses testified that Ploni knocked out his slave's tooth and afterwards blinded his eye, and they were Huzam, they pay to Ploni the value of the slave and his eye.

Rebuttal (Ra'avad): The Rambam (Hilchos Chovel 4:11) rules that the master need not pay for the eye, just if the slave seized it, he need not return it. If so, why do witnesses pay?!

Kesef Mishneh: They pay because it is likely that the slave will seize (since he keeps it).

Rambam (Hilchos Nizkei Mamon 11:1): If a slave must go free but needs a document of freedom, there is no fine (if an ox gored and killed him).

Question (Magid Mishneh): Why didn't he Rambam teach that if the master seized the fine, we do not force him to return it? This is the law for matters that the Gemara left unresolved, even for fines!

Answer (Ohr Some'ach): Fines require testimony she'Efshar Lehazimah. We cannot obligate witnesses to pay, for they can say 'we did not expect that the victim will seize the money.' This is unlike a master who destroyed his slave's tooth and eye. Surely the witnesses intended that the slave be paid for his eye. If they wanted only to free him, it would have sufficed to testify about the tooth alone! Here, they can say 'we wanted only to get the ox stoned.'

Note: To stone the ox without obligating money, it would have sufficed to say that the ox gored a convert without heirs, or they could not identify the victim. Perhaps they said that it gored the slave to make their testimony more credible, e.g. it was known that the slave died through an injury of unknown cause. However, we cannot give this answer if the slave was overseas, or it was assumed that he drowned, or died on his bed.

Ohr Some'ach (Hilchos Edus 11:6): If we do not punish Edim Zomemim for causing that if the claimant seized the money, he keeps it, according to those who require Efshar Lehazimah for monetary cases, testimony of Pesulim mid'Rabanan does not help mid'Oraisa! The witnesses can say that they did not expect him to seize; the Nitva should have ensured that he not seize. The enactment for Ne'ilas Delet (not to require Drishah v'Chakirah, lest potential lenders be deterred) does not apply here. One will not lend, hoping to seize the money back (if his only witnesses are Pesulim mid'Rabanan)! Therefore, even mid'Rabanan the testimony is Batel. Even if he seized before the witnesses came, and they say that he may keep it, since Beis Din initially needed to take the money from him, we do so even after the Pesulim testify, for it is theft mid'Rabanan.

Rambam (Hilchos Rotze'ach 2:9): Any testimony she'Iy Efshar Lehazimah is invalid for capital cases.

Ohr Some'ach (Hilchos Edus 4:1): I am unsure about one who killed without witnesses, i.e. without warning or the witnesses did not see each other. (In such cases we put the murderer in Kipah (a cell) and cause him to die). Does Hazamah apply to put the witnesses in Kipah? Presumably, we do not. Even though the testimony is Iy Efshar Lehazimah, we can answer like Tosfos (Makos 2a), that lashes fulfill Ka'asher Zomam, or that testimony she'Iy Efshar Lehazimah is Kosher for monetary (i.e. all non-capital) cases, like the Rambam connotes in Hilchos Rotze'ach (2:9).

Ramban (Bava Basra 56a DH u'Mah): If three different pairs of witnesses testified about each of the three years of Chazakah, if only one or two of them were Huzam, we do not punish them. If all of them were Huzam, we punish them. If not, the testimony would be Iy Efshar Lehazimah!

Question (Ramban Makos 5a DH veha'Ge'onim): Ge'onim (and our text of R. Chananel) explain that if a pair of witnesses (B) was Mezim pair A, and pair C was Mezim B, R. Yehudah does not accept Hazamah against C. If so, C's testimony is Batel, for it is Iy Efshar Lehazimah! Also B's testimony is Batel, for we cannot be Zomem the Zomemim, just like Treifah witnesses who were Huzmu are not killed!

Answer (Ramban): There, we could not punish the witnesses (who were Mezim the Tereifos) even if we knew that they were Huzam. Here we Mevatel the testimony only because we suspect a conspiracy. If we knew that it is true, we would fulfill Ka'asher Zomam! Rather, since the testimony is so confused, we disqualify all of the witnesses retroactively.

R. Akiva Eiger (1:179): All agree that women and relatives are Kosher for testimony about a Sotah or Edus Ishah (testimony that a man died, to permit his widow). If so, why doesn't Shevu'as ha'Edus apply to them? We must say that "v'Hu Ed" applies only to Kosher witnesses who can testify about anything. Likewise, Hazamah applies only to Kosher witnesses, for it says "v"Ed Sheker ha'Ed" and "Lo Sa'aneh b'Re'echa Ed Shaker." If a litigant accepted one Kosher witness to be like two (against him), Hazamah applies. However, the Ran says that Shevu'as ha'Edus does not apply in such a case. Presumably, also Hazamah does not apply. The Rambam says that Hazamah applies to one witness who testified about Zenus after warning and seclusion. This is because letter of the law, he is believed.

Ritva (Makos 2a DH v'Ha): Really, Hazamah mid'Oraisa does not apply to a Ben Chalutzah, for he is Kosher mid'Oraisa. The Tana merely taught Chalutzah along with Gerushah.

Rebuttal (R. Akiva Eiger ibid.): Even though mid'Oraisa he is Kosher, the testimony worked to disqualify him mid'Rabanan!