Sefer HaChinuch ספר החינוך

To not conclude the judgment by estimation: That a court only kill the accused with witnesses that testify about the same matter about which he is to be killed; that they actually saw him with their eyes, [not] that they testify against him based on strong indications. And about this is it stated (Exodus 23:7), “and an innocent one and a righteous one you shall not kill” — meaning to say, be very careful not to kill a person about whom it is possible that he did not do what they said that he did. And so is it explained in Mekhilta DeRabbi Yishmael 23:7:2, as there they said, “If they saw him pursuing another to kill him, the knife in his hand, and they [warned him, ‘If you kill him, you will be killed.’ And the witnesses] averted their eyes [and did not see him striking him] and afterwards they found him (the victim) in the death throes, the knife dripping blood in the hand of the murderer — I might understand that he is liable [for execution. Hence,] we learn to say, ‘and a clean one and righteous one you shall not kill.’” Behold, because they averted their eyes at the time of the striking, this one is exempted. And the matter is proper and fitting to be like this. As if the Torah had permitted to establish the parameters of punishment with strong possibilities, it would come out from the matter that sometimes we would kill people for something they did not do, as there is great breadth to the possible. And know this and understand it, as it is a clear thing. And therefore, He, may He be elevated, closed this gate and commanded us about it. And all of “the precepts of the Lord are just, rejoicing the heart” (Psalms 19:9). And also included in this negative commandment is one about whom two witnesses have testified that he committed a [different] sin; for example, that one testifies that he did work on Shabbat and one testifies that he worshiped idolatry, such that this one is not condemned by their testimony, as it is stated, “and an innocent one and a righteous one do not kill.” And so did they, may their memory be blessed, say (Mekhilta DeRabbi Yishmael 23:7:2), “If one testified against another that he worshiped the sun, and another, [that he worshiped] the moon, I might understand that they combine (to constitute the necessary two witnesses). [Hence,] we learn to say, ‘and an innocent one and righteous one you shall not kill.’”

The root of this commandment is revealed to all, as we have said.

Its laws — that which they, may their memory be blessed, said (Makkot 6b), that their testimony is not combined even if they testify about the same sin unless they both saw it [together]; also that they saw each other at the time of the act, to exclude if this one saw it from this window and the other from another window and they could not see each other, but the one who gives the warning combines them if he saw both of them; and the rest of its details — are in Sanhedrin.

And [it] is practiced in the Land of Israel by males, since justice is with them, as we have said many times; but not by females, as they do not judge. And one who transgresses it and judges according to testimony that is not precise — as we have said — has violated a commandment of [the] King. And his punishment is very great, as he causes souls to be killed, not according to the law. And Ramban (on Sefer HaMitzvot, Negative Commandments 290), may his memory be blessed, counted this verse as two negative commandments about a different matter. And that is that [the accused] is exempted in capital cases, in ways through which he would be liable in monetary cases. And he relied upon that which they said in the Gemara (Sanhedrin 33b), “The Sages taught, ‘From where is it derived that one who is leaving the court liable, and someone said, “I can advocate his innocence,” that we bring [the accused] back [to be judged again]? The verse states, “and an innocent one you shall not kill”’” — meaning to say [that] this one is innocent, as maybe this one will advocate that he is innocent. “And from where is it derived that one who is leaving the court innocent, and someone says, ‘I can advocate his guilt,’ that we do not bring [the accused] back [to be judged again]? The verse states, ‘a righteous one you shall not kill’” — and this one is righteous, as he already left [the court] righteous (innocent). And all of these matters are from the root that I have written — that God wanted us to mull every merit for the accused, as he may repent and regret the evil that he did and become from those that civilize the world. And He, blessed be He, desires its civilization.