Once again, James draws us into the world of Jesus. James 5:6 reads: “You have condemned and murdered innocent men, who were not opposing you.” A more literal reading, here quoting from the NASB, tells a different story: “You have condemned and put to death the righteous man; he does not resist you.” The NIV generalizes this into humans; the NASB translates as a singular because the Greek is singular. Perhaps “the righteous man” represents the righteous person and stands for all those who have been oppressed.
We should observe that they have, as they did in James 2:1-7, condemned the innocent/righeous person. This speaks of legalities and of power and of the abuse of power.
Some have suggested the condemned righteous/innocent is (1) representative of all suffering righteous persons, (2) James himself or (3) Jesus. I believe the first option is best, and that James uses a present tense for the “is not resisting” and “is crying out” in 5:4 slightly confirms this viewpoint.