Deuteronomy 21:9

9 Then you will have removed from yourselves the guilt of murdering an innocent person, because you will be doing what the Lord says is right.

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 They should declare: "We did not kill this person, and we did not see it happen.

8 Lord, remove this sin from your people Israel, whom you have saved. Don't blame your people, the Israelites, for the murder of this innocent person." And so the murder will be paid for.

9 Then you will have removed from yourselves the guilt of murdering an innocent person, because you will be doing what the Lord says is right.

10 When you go to war against your enemies, the Lord will help you defeat them so that you will take them captive.

11 If you see a beautiful woman among the captives and are attracted to her, you may take her as your wife.