This verse includes three separate instructions:
(1) You shall not be partial in judgment; you shall hear the small and the great alike. New Revised Standard Version rightly places a colon instead of a semicolon after “judgment,” since what follows is a further elaboration of the first item. By small and great is meant the lowly, poor, powerless people, as opposed to the important, wealthy, influential members of the community. It is possible to reverse the order of these two clauses: “It doesn’t matter if one person is poor [or, helpless] and the other is powerful [or, wealthy], you must judge impartially.”
(2) You shall not be afraid of the face of man, for the judgment is God’s. Again, New Revised Standard Version is much clearer in English: “You shall not be intimidated by anyone”; this is more simply “Don’t be afraid of anyone” (Contemporary English Version). And the reason for this instruction is that judgment is given in God’s name and with God’s authority. In this community in which God’s laws ruled the people, any enforcement of the law was an application of God’s will. So Good News Translation has “for the decision you make comes from God.” Another way to express this is “For God will help you to make the right [or, correct] decision.”
(3) And the case that is too hard for you, you shall bring it to me, and I will hear it. The meaning here is quite clear; Moses will hear—that is, decide, settle, judge—any dispute that is too difficult for the appointed judge to handle. The clause you shall bring it to me can be taken to mean “bring the people to me” (Contemporary English Version), as it is two people who are having a dispute. And this final sentence may thus be expressed as “If any dispute is too difficult for you to decide, bring the people who are involved to me and I will make the decision.”

Quoted with permission from Bratcher, Robert G. and Hatton, Howard A. A Handbook on Deuteronomy. (UBS Helps for Translators). New York: UBS, 2000. For this and other handbooks for translators see here .