JOS 20:6

6 But the person who killed someone must stay in that city until the city judges put him on trial. [Only if the judges decide that the person who has run/escaped to their city did not deliberately kill the other person will they allow him to stay in that city], and he must stay there until the Supreme Priest dies. Then he may safely go back to his own town, [because the death of the Supreme Priest will be considered to atone/pay for the death of the person who was killed].”