Deuteronomy 16:20 includes what has to be among the most quoted passages in Torah: "Justice, justice shall you pursue." Jeffrey Tigay, in his JPS Commentary, interprets the passage to mean: "That is, justice alone, and only justice." The redundancy is thus understood as lending strong emphasis to this most basic principle in our Tradition.
Talmud Sanhedrin offers two way of understanding the redundancy: 1) to teach the judges to probe deeply to find the justice through careful investigation and inquiry; 2) to instruct the judges to seek justice, either through rendering a judgment or through a settlement based on compromise.
Rashi, however, quoting the Sifre, suggests that the words are not addressed to the judges in a court, but to the litigants, who are instructed to extend themselves to find a reliable court, and the repetition is intended to convey the need to search hard for such a tribunal.
The Hassidic master, Rabbi Simha Bunem, offers a different suggestion that deals less with procedural matters than with ethics: "Pursue justice justly." That is the means that lead us to justice must, themselves, be just. Pursuing justice through unjust means negates the justness of the process and only adds to the injustice that corrodes society.
I believe that Rabbi Simha may have picked up on an important message that our Parashah conveys in the paragraphs that immediately follow this passage. Immediately after the opening of Parashat Shof’tim, with its instructions to set up courts of justice that render judgment justly and with uncompromising integrity, the Torah turns to a series prohibitions that are related to improper worship. Dt. 16:21-22 prohibits the erecting of forbidden posts and pillars in the place where God is worshipped. These are the implements of idolatry, which Deuteronomy, in particular, considers to be the most heinous of crimes. Dt. 17:1 forbids the offering of blemished animals as sacrifices, and then 17:2-7 provides instructions on how to deal with a person who has actually been found violating the prohibitions against idolatry (vv. 2-3). We read that the judge is supposed to thoroughly investigate the charge (v. 4), and, if it has been proven to be true, the guilty party is to be brought to the gate of the city, where he or she shall be stoned to death (v. 5). This punishment shall be carried out only if there are a minimum of two witnesses, and, to insure that they are, indeed, telling the truth, they, the witnesses, shall cast the first stones (vv. 6-7).
How does this dovetail with Rabbi Simha Bunem’s interpretation? One might have thought that if a person is caught worshiping idols and, thus, violating two of the most essential laws of Torah, the belief in and worship of only the One God, and the prohibition of idol worship or polytheism of any kind (which comprise the first of the Ten Commandments), then a true believer may be given permission to kill the idolater on the spot. This would parallel the law of the rodef, the pursuer, who intends to do bodily harm to another person, who can even be killed by a third party without benefit of trial. But the Torah here is teaching us that this is not the case. Even in the case of the perpetration of this most horrific of crimes, a crime which undermines the very foundation upon which Torah religion and Israelite society are based, the process of justice must be carried out. No vigilantism here, nor any diminution of the rights of the accused to a fair trial, with proper investigation and testimony. God is a God of justice, says Deuteronomy, and to introduce injustice into the fabric of society is tantamount to idolatry, because it is a denial of one of the essential attributes of the One God, an attribute that sets God apart form the false gods of the pagan world.
What is the most heinous crime of our time? Many people would say terrorism, because it entails the murder of large numbers of innocent people in an effort to undermine the foundations of a society. If captured alive, should terrorists be killed on the spot, or are they entitled to a trial in which all the procedures of justice are in operation? Deuteronomy’s answer is clear: "Justice, justice shall you pursue, that you may live and inherit the land that the Lord your God is giving to you." It is just to seek to eradicate terror, but this must be done justly. Then, and only then, will the foundations of a just society remain intact, and then and only then will the inhabitants of a land be able to live in it.