Romans 12:17-21
7 Repay no one evil for evil. Have regard for good things in the sight of all men.
18 If it is possible, as much as depends on you, live peaceably with all men.
19 Beloved, do not avenge yourselves, but rather give place to wrath; for it is written, “Vengeance is Mine, I will repay,” says the Lord.
20 Therefore “If your enemy is hungry, feed him; If he is thirsty, give him a drink; For in so doing you will heap coals of fire on his head.”
21 Do not be overcome by evil, but overcome evil with good.
I Thessalonians 5:15
15 See that no one renders evil for evil to anyone, but always pursue what is good both for yourselves and for all.
I don’t think the evil spoken of in those verses speak to the taking of innocent life; especially if one tries to reconcile verse 18 with verses 17 and 21.
Imposing consequences for great evil is not evil.