Deuteronomy 19:6; Deuteronomy 19:12

6 Otherwise, the avenger of blood might pursue him in a rage, overtake him if the distance is too great, and kill him even though he is not deserving of death, since he did it to his neighbor without malice aforethought.

12 the killer shall be sent for by the town elders, be brought back from the city, and be handed over to the avenger of blood to die.