Rashi on Numbers 35:27/רש"י על במדבר ל״ה:כ״ז

1אין לו דם [AND THE AVENGER OF BLOOD MAY SLAY THE MURDERER] THERE IS NO BLOOD GUILT FOR HIM (more lit., he has no blood) — He is as one who has killed a dead man, who is one who has no blood (cf. Rashi on Exodus 22:1).