Cross reference
Numbers 35:27
27 and the avenger of blood find him outside of the border of his city of refuge, and the avenger of blood kill the manslayer; he shall not be guilty of blood,
Exodus 22:2
2 If the thief is found breaking in, and is struck so that he dies, there shall be no guilt of bloodshed for him.
Deuteronomy 19:6
6 lest the avenger of blood pursue the manslayer, while his heart is hot, and overtake him, because the way is long, and strike him mortally; whereas he was not worthy of death, inasmuch as he didn't hate him in time past.
Deuteronomy 19:10
10 that innocent blood not be shed in the midst of your land, which Yahweh your God gives you for an inheritance, and so blood be on you.