Perverting Justice against a Convert or Orphan

"You shall not pervert the judgment of the stranger or the orphan"Deuteronomy 24:17.

A judge is forbidden to unlawfully rule against a convert or orphan [taking advantage of their powerlessness].

Though it is forbidden to pervert justice no matter the identity of the defendant, a judge who does so in that case of a convert or orphan, transgresses also this additional prohibition.

Equal Treatment for Litigants

"With righteousness, judge your neighbor"Leviticus 19:15.

The judge presiding over a case must treat both litigants equally, giving each the opportunity to speak whatever is on his mind—whether he speaks briefly or at length.

Also included in this mitzvah is the obligation on a qualified judge who is versed in Torah's legal code to issue a verdict. This obligation takes effect as soon as the two litigants present their arguments before him.

And also included in this mitzvah is that every individual is commanded to give his fellow the benefit of the doubt, and, when circumstances allow, to interpret his fellow's actions or words in a favorable light.

Fearless Justice

"You shall not be afraid before any man"Deuteronomy 1:17.

A judge may not fear an evil and dangerous individual, ruling in his favor because he's concerned that he may exact revenge against him. As the Midrash says, "Perhaps you will say, 'I fear that individual for perhaps he will kill my son, set my barn afire, or destroy my crops'—therefore the Torah says, 'You shall not be afraid before any man!'"

Bribery

"And you shall take no bribe"Exodus 23:8.

A judge may not accept a gift from any of the parties in a case—even if the gift is given on condition that he rules justly [i.e., the party presenting the gift clearly states that it does not expect – or want – to be favored in any way].