What do you mean by "righteous" and "unrighteous" people? If you mean people who are actually, in and of themselves righteous, your error is easily disprovable by pointing out that Paul clearly called himself a wicked man, even after conversion (Rom 7:24). Paul was righteous only according to faith, and that is true for all believers, no matter the age, because all fall short of the glory of God.
By “righteous” and “unrighteous” people I mean people who are or who are not practicing righteousness—as in John 3:7,
Little children, make sure no one deceives you; the one who practices righteousness is righteous, just as He is righteous;
Consider also,
Acts 10:34. And Peter opened his mouth and said: “Truly I perceive that God shows no partiality,
35. but in every nation any one who fears him and does what is right is acceptable to him.”
Paul NEVER called himself a wicked man! Indeed, to do so would have been to blaspheme our Lord and savior Christ Jesus who redeemed him from bondage to sin and gave him a new life! Perhaps you are thinking of this passage,
Romans 7:14. We know that the law is spiritual; but I am carnal, sold under sin.
15. I do not understand my own actions. For I do not do what I want, but I do the very thing I hate.
16. Now if I do what I do not want, I agree that the law is good.
17. So then it is no longer I that do it, but sin which dwells within me.
18. For I know that nothing good dwells within me, that is, in my flesh. I can will what is right, but I cannot do it.
19. For I do not do the good I want, but the evil I do not want is what I do.
20. Now if I do what I do not want, it is no longer I that do it, but sin which dwells within me.
21. So I find it to be a law that when I want to do right, evil lies close at hand.
22. For I delight in the law of God, in my inmost self,
23. but I see in my members another law at war with the law of my mind and making me captive to the law of sin which dwells in my members.
24. Wretched man that I am! Who will deliver me from this body of death?
25. Thanks be to God through Jesus Christ our Lord! So then, I of myself serve the law of God with my mind, but with my flesh I serve the law of sin.
If Paul is, in this passage, writing of himself after he was redeemed from bondage to sin and given a new life in Christ, who sold this redeemed man under sin (v. 14)? Did you? Did Calvin? Did Satan? What an absurd thought!
The truth is that Paul is, in this passage, using the literary device known as “speech in character”—in this case, the character of an upright Jew who delights in the Law (as all upright Jews do) and who is striving unsuccessfully to do right by obeying the Law. Christians do NOT strive to obey the Law—because the just requirement of the law is fulfilled in us! (Rom 8:4).
Paul was righteous because he had been justified by faith; he was also righteous because, having been enabled to through his rebirth in Christ, he practiced righteousness. And that is true of all Christians.
The linguist and Bible scholar Adam Clarke wisely wrote in his commentary of the Bible,
It is difficult to conceive how the opinion could have crept into the Church, or prevailed there, that “the apostle speaks here of his regenerate state; and that what was, in such a state, true of himself, must be true of all others in the same state.” This opinion has, most pitifully and most shamefully, not only lowered the standard of Christianity, but destroyed its influence and disgraced its character. It requires but little knowledge of the spirit of the Gospel, and of the scope of this epistle, to see that the apostle is, here, either personating a Jew under the law and without the Gospel, or showing what his own state was when he was deeply convinced that by the deeds of the law no man could be justified, and had not as yet heard those blessed words: Brother Saul, the Lord Jesus, that appeared unto thee in the way, hath sent me that thou mightest receive thy sight, and be filled with the Holy Ghost, Act_9:17.
(All quotations from Scripture are from the RSV, 1971)