Justice is a central concern of the prophets, notably Micah 6:8 and Isaiah 1:17.
In Micah 6:8:
8 He hath shewed thee, O man, what is good; and what doth the LORD require of thee, but to do justly, and to love mercy, and to walk humbly with thy God?
In Isaiah 1:17:
17 Learn to do well; seek judgment, relieve the oppressed, judge the fatherless, plead for the widow.
In Proverbs 21:15:
15 It is joy to the just to do judgment: but destruction shall be to the workers of iniquity.