The Brothers Karamazov is narrated by a chronicler, a resident of the town, who writes in the first person thirteen years after the events and who, before telling anything, apologizes for having chosen such an unremarkable hero.
In the preface, he says that Alyosha is not a great man and that the biography is one, but the novels are two: the first, from thirteen years earlier, is needed to understand the second. He calls the hero eccentric and says that sometimes the eccentric carries within himself the core of the whole. He shows himself willing to lose the reader: he gives him, as a courtesy, the right to drop the book at the first episode.
He tells what he saw and what he was told, admits what he does not know, interrupts scenes to explain what Alyosha felt, and confesses, at the trial, that he has no strength to tell everything. He includes in the book a manuscript by Alyosha, the life of Elder Zosima, written from memory, and warns that he does not know whether everything was said that afternoon or added later.
The choice has an effect: the reader reads the decisive scenes with the doubt of one who tells them. The chronicler loves Alyosha, treats Fyodor with irony and, when he speaks of the prosecutor and the court, lets it show what he thinks. He does not decide for us, but neither does he let the facts speak alone.