The foundational Noahide principle of Bereishit 9:5 demands an accounting for every human life taken — "from the hand of every man, his brother, I will demand the soul of man" — establishing that bloodshed carries divine consequence regardless of the victim's identity.
Vayikra 24:17–22 declares that "anyone who kills any human being shall be put to death" and that there shall be "one standard for stranger and citizen alike," articulating what appears to be a universal rule of equal accountability before God.
Yet the Gemara in Sanhedrin 57a presents a baraita that draws a sharp distinction by category of perpetrator and victim: a gentile who kills another gentile, or a gentile who kills a Jew, is liable under Noahide law, while a Jew who kills a gentile is — in the baraita's term — exempt (פָּטוּר) from human court liability; the Gemara itself wrestles with how the tanna should have phrased this, rejecting language of "permitted" as clearly too broad, yet retaining the technical exemption from capital punishment by beit din.
Mishneh Torah, Murderer and the Preservation of Life 2:11 codifies this distinction explicitly: one who kills a ger toshav is not executed by beit din, as derived from the verse "if a man acts intentionally against his fellow" (Shemot 21:14), and it adds that this is certainly true regarding the killing of an idolater — though it pointedly records that one who kills another's slave is executed because the slave "accepted mitzvot and was added to God's inheritance."
Mishneh Torah, Murderer and the Preservation of Life 2:1 establishes, for contrast, the baseline rule that any person who kills his fellow Jew directly — by sword, stone, strangulation, or fire — is executed by beit din, making clear that the exemption recorded in 2:11 is a deviation from the general capital rule rather than the norm.
Shulchan Arukh, Choshen Mishpat 425:1 addresses the rodef principle — the obligation to stop a pursuer even by lethal force before he kills — but this law operates only while the threat is active; the passage's own framing confirms it does not extend to punishment after the danger has passed, which is precisely the scenario under discussion.
Netivot Olam, Netiv HaDin 1:1 reflects on justice as the very embodiment of righteousness, citing Mishlei that "it is a joy to the righteous to do justice and a terror to evildoers," underscoring that while beit din's technical jurisdiction may be limited, the moral demand for justice remains foundational to the Torah's worldview — and the absence of human court punishment is emphatically not the same as moral license or divine indifference.