What has already been paid for is our "debt" to God. Like I said, that does not mean you don't have to suffer the physical consequences of your sin.
I think you are confusing spiritual death, or the second death, meaning hell for eternity and physical death, the first death, that relates to our bodies.
Like some other poster quoted, "But if you do evil, be afraid; for he does not bear the sword in vain; for he is God’s minister, an avenger to execute wrath on him who practices evil" (Ro. 13:4).
Of course, civil law is necessary, but I argue against “punishment” as a justification for CP and believe the effort should be towards protecting society.