In my college class, a girl asked the other day, “How can you be for the death penalty if you are pro-life?” She also said the Bible says don’t judge, so how can you use the death penalty (because you would be judging). I was trying to find out the correct way to let her know that you can be pro-life and for the death penalty.
The point of being pro-life is that we put the same high value of all life that God does, from the earliest pre-born baby to the last breath of an elderly, dying person. We derive our high value of life from the fact that every human being is made in the image of God. Thus, when someone takes the life of another in murder, they are treating the person they murdered as less important and valuable than they are. God instituted the death penalty Himself after the flood when He said, “Whoever sheds man’s blood, by man his blood shall be shed, for in the image of God, He made man.” (Gen. 9:6)
The reason the death penalty is pro-life is that it puts the highest possible value on the life of the person murdered by exacting the life of the person who violated that value by murdering. It’s a strong way to say, “It is not OK for one human being to take the life of another. If you murder, you forfeit your own life because the person you killed is so valuable.”
Concerning judging: yes, the Bible does say don’t judge, but it also commands us to judge rightly. So you have to look at the context of commands such as “Judge not, lest ye be judged” (Matt. 7:1), which is about condemning others for doing the very same thing we do. Judging also means “be discerning” and “make a distinction between right and wrong.” Jesus repeatedly taught men to judge rightly, insisting they “judge with righteous judgment” (John 7:24). He praised a man who “rightly judged” (Luke 7:43). Jesus also said, “And if your brother sins, go and reprove him, and if he refuses to listen, tell it to the church” (Matt. 18:15,17). Obeying such a command is only possible by making a judgment on one who sins. Jesus’ apostle Paul later gave God’s command to the church: “Do you not judge those who are within the church? . . . Remove the wicked man from among yourselves” (1 Cor. 5:12,13).
Also, the Bible tells us that governments (which are the only entities entitled to carry out capital punishment) are instituted by God for maintaining order: “[F]or [government] is a minister of God to you for good. But if you do what is evil, be afraid; for it does not bear the sword for nothing; for it is a minister of God, an avenger who brings wrath on the one who practices evil. (Rom 13:4)
Thus, I would argue that the Bible supports capital punishment, although it is extremely important to make absolutely sure that only the guilty are executed.
Hope this helps!