A rodef (Hebrew: רודף, lit. "pursuer"; pl. רודפים, rodfim), in traditional Jewish law, is one who is "pursuing" another to murder him or her. According to Jewish law, such a person must be stopped—even killed—by any bystander after that pursuer has been warned and refuses to stop. A source for this law appears in the Babylonian Talmud:
And these are the ones whom one must save even with their lives [i. e., killing the wrongdoer]: one who pursues his fellow to kill him [rodef achar chavero le-horgo], and after a male or a betrothed maiden [to rape them]; but one who pursues an animal, or desecrates the Sabbath, or commits idolatry are not saved with their lives.[1]
This law, the din rodef ("law of the pursuer"), is significant as one of the few provisions in Jewish law permitting extrajudicial killings.
The allowance to kill the rodef does not apply, however, in a case where lesser means would prevent the innocent's murder.[2] Furthermore, according to Maimonides, killing a rodef who may have been stopped by lesser means constitutes murder, though the punishment for a murderer in this case is not dealt out by beit din.[3]