The Torah commands in Parashat Ki-Teseh (Debarim 2416), “Lo Yumtu Abot Al Banim, U’banim Lo Yumtu Al Abot” – “Fathers shall not be killed because of their sons, and sons shall not be killed because of their fathers.” This verse is understood to mean that a court is not permitted to put a defendant to death based on the testimony of his parent or child.

Although the Torah speaks here specifically of testimony regarding a capital crime, this command in truth includes all court cases, even cases involving financial disputes. A Bet Din is forbidden by force of this command from acting upon testimony given by a witness about a family member. The Torah gives the example of a capital case because one might have assumed that a person would not testify untruthfully about his family member’s capital offense, which would lead to his or her execution. Since we would have thought to accept testimony incriminating one’s family member of a capital crime, the Torah introduced this command specifically in the context of an offense incurring the death penalty.

Likewise, although the Torah speaks here of a parent testifying about a child, and a child testifying about a parent, this prohibition actually applies to testimony about any family member. The example of a parent and child is given because of the strong feelings of love and affection that exist between parents and children. We might have thought to accept incriminating testimony about one’s parent or child, because it is difficult to imagine that one would falsely testify against one’s parent or child. The Torah therefore gave this particular example, but the prohibition applies also to other family members.

The Sefer Ha’hinuch explains that the Torah forbade accepting testimony about family members in order to help ensure the veracity of testimony accepted in courts of law. A stable society requires a functioning judicial system, and so it is imperative that courts act upon testimony which cannot be questioned. Therefore, the Torah forbade accepting testimony on behalf of family members, as family members might lie in order to help one another. The Sefer Ha’hinuch writes that the Torah extended this prohibition to include also incriminating testimony against family members as a safeguard against accepting testimony given on behalf of family members. If the Torah allowed accepting incriminating testimony, courts might then begin accepting even testimony on behalf of family members, and so the Torah disqualified all testimony about the witness’ family members.

Additionally, the Sefer Ha’hinuch writes, family members generally live with one another, which frequently gives rise to tensions and fighting. When friction arises, a person might decide to come to court and falsely testify about his family member towards whom he feels resentment. He will then later regret having brought the false accusation, once his anger subsides. The Torah therefore commanded that testimony about family members must not be accepted.

On the level of Torah law, this disqualification applies only to paternal relatives – father and son, grandfather and grandson, paternal brothers, the sons of brothers, and a man with his brother’s son. The Rabbis extended this prohibition to include also family members related maternally, or through marriage. According to some opinions, however, even these relationships are included in the Biblical prohibition.

Regardless, it is clear that brothers and first cousins may not testify about one another. Second cousins, however, may testify about one another. A second cousin may testify about his second cousin’s parent, and vice-versa. According to some opinions, although one may not testify about a grandparent or grandson, one may testify about a great-grandparent or great-grandson. Others, however, maintain that when it comes to a family’s direct line, testimony is invalid even about somebody three or more generations removed.

Anytime a person is ineligible to testify about a woman due to a familial relationship, he is also ineligible to testify about her husband. Likewise, if someone cannot testify about a man due to their familial relationship, he may not testify about his wife. Thus, for example, just as one cannot testify about his wife’s sister, he may not testify about her husband. However, one may testify about that husband’s family members.

If a man betrothed a woman (Erusin), they may not testify about one another, even before they marry.

At my wedding, two Rabbis served as witnesses – Rabbi Max Maslaton and Rabbi David Ozeri. It was later determined that since Rabbi Maslaton and Rabbi Ozeri’s wife are first cousins, they are considered relatives, and are thus disqualified to serve as witnesses together. As such, the betrothal ceremony needed to be repeated with different witnesses. This is an example of the Halacha mentioned above, that a disqualifying familial connection with a woman is applied also to her husband.

This prohibition applies even today, when witnesses are brought before a Bet Din in cases involving financial disputes. It applies to the judges of the Bet Din, forbidding them from accepting the testimony of a litigant’s family member. Of course, they are not liable to Malkut for this transgression, as it is committed without performing an action (“Lav She’en Bo Ma’aseh”).

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253 Dipping One's Head In Tefilah - נפילת אפיים