There is one word which can accurately describe the DUP-Sinn Fein ruling elite: "unhappy".
Would it be too radical to suggest that less-happy people find meaning in Old Testament laws and that happier people are like those described by Jesus in the Sermon on the Mount?
A desire to re-introduce the death-penalty on the part of the DUP informs us that they're still attached to the Old Testament ways of "an eye for an eye".
Sinn Fein isn't far behind. It would be much happier if it just admitted the misery it once caused rather than repeatedly justifying it. Unfortunately, unhappy people are very difficult to change.