I do not care what justice is "to you"!
It is not a matter of opinion.
You just now, in the sentence IMMEDIATELY prior to this, said that your opinion had something to do with the bible.
Which parts of the bible do you read and which do you ignore?
Maybe read the following....
Deuteronomy 32:35 Vengeance is Mine, and recompense; Their foot shall slip in due time; For the day of their calamity is at hand, And the things to come hasten upon them.’
Deuteronomy 32:41 If I whet My glittering sword, And My hand takes hold on judgment, I will render vengeance to My enemies, And repay those who hate Me.
Romans 12:19 Beloved, do not avenge yourselves, but rather give place to wrath; for it is written, “Vengeance is Mine, I will repay,” says the Lord.
Hebrews 10:30 For we know Him who said, “Vengeance is Mine, I will repay,” says the Lord. And again, “The Lord will judge His people.”
Capital punishment is NOT about vengeance, at least not directly.
Whether any of that is valid has nothing to do with it being your opinion or because of what you do or do not see.
No one cares what your personal opinions are. Make an argument. Risk being right and take a stand on something more firm than something as thin and flimsy as  personal opinions.