Deuteronomy 21:9

9 And thou shalt take away innocent blood from among you, if thou shouldest do that which is good and pleasing before the Lord thy God.

Deuteronomy 21:9 Meaning and Commentary

Deuteronomy 21:9

So shalt thou put away the guilt of innocent blood from among
you
Which otherwise, the person not being found out, and brought to just punishment for it, would devolve upon the whole. Aben Ezra interprets it the punishment of innocent blood, which, by the above method being taken, would not be inflicted on them:

when thou shalt do that which is right in the sight of the Lord;
as it was to observe this law concerning the beheading of the heifer, with all the rites and ceremonies belonging to it here enjoined; as well as every other command, statute, and ordinance of the Lord, which are all right to be done, ( Psalms 19:8 ) .

Deuteronomy 21:9 In-Context

7 and they shall answer and say, Our hands have not shed this blood, and our eyes have not seen .

8 Be merciful to thy people Israel, whom thou hast redeemed, O Lord, that innocent blood may not be charged on thy people Israel: and the blood shall be atoned for to them.

9 And thou shalt take away innocent blood from among you, if thou shouldest do that which is good and pleasing before the Lord thy God.

10 And if when thou goest out to war against thine enemies, the Lord thy God should deliver them into thine hands, and thou shouldest take their spoil,

11 and shouldest see among the spoil a woman beautiful in countenance, and shouldest desire her, and take her to thyself for a wife,