Deuteronomy 19:10

19:10 You must not shed innocent blood in your land that the Lord your God is giving you as an inheritance, for that would make you guilty.

Deuteronomy 19:12-13

19:12 The elders of his own city must send for him and remove him from there to deliver him over to the blood avenger to die. 19:13 You must not pity him, but purge out the blood of the innocent from Israel, so that it may go well with you.

Deuteronomy 21:9

21:9 In this manner you will purge out the guilt of innocent blood from among you, for you must do what is right before the Lord.