You’re living under the Old Covenant of the law which was done away at the cross of Christ (Heb. 8:7, 13), replaced by the New Covenant of grace (Heb. 8:8-12), of which you seem to hold yourself out to be some kind of minister.
Romans 13:1-4 Let every person be subject to the governing authorities. For there is no authority except from God, and those that exist have been instituted by God. Therefore whoever resists the authorities resists what God has appointed, and those who resist will incur judgment. For rulers are not a terror to good conduct, but to bad. Would you have no fear of the one who is in authority? Then do what is good, and you will receive his approval, for he is God's servant for your good. But if you do wrong, be afraid, for he does not bear the sword in vain. For he is the servant of God, an avenger who carries out God's wrath on the wrongdoer.
The sword is for law enforcement. Under your paradigm, if murderers are not punished, then nobody should be.
Why punish any crime then? Just forgive it all.
How's that working out these days?
Besides, the God given death penalty predates the Law and stands outside it. So the accusation of living under the Law falls flat.