Is justice a common noun

The noun 'justice' (lower case j) is a common noun as a general Word for a judge or a magistrate; a general Word for a quality of fairness and reason; a Word for any justice of any kind.

The noun 'Justice' (capital J) is a proper noun as the title of a specific person; for example, John Roberts, Chief Justice of the United States or Susan Kiefel, Chief Justice of Australia. Justice Kiefel has served in the courts of Australia since 1993.