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A little context: the quote comes from the movie made based on John Grisham's A Time to Kill, as spoken by lawyer Jake Brigance. The story is based on the events surrounding the trial in Clanton, Mississippi of a black man accused of murdering the two white men who raped and beat his ten-year old daughter. Jake is one of the team of lawyers arguing for the defense in the trial, and the quote is part of his closing statement.
The quote is arguing that, as long as people continue to find differences between themselves and others, true justice will never be achieved. If people regard each other with suspicions based on prejudices, even if they are not outwardly demonstrated, there will be opinions and feelings influencing the process of determining justice.