In short, Coetzee renders the magistrate as a person aware of his own guilt and conscious of all the tangled complexities of his situation as a peace-loving official in the service of a violent and exploitative empire. Juxtaposed to Colonel Joll's unreflective and unyiedling confidence in the empire's justifications for torture and for waging an offensive war against the barbarians, the magistrate's complex reflections are posed in the novel as being relatively honest and even brave.
The self-questioning posed in the narration presented by the magistrate is never one that exonerates him from complicity or from guilt. This trait makes the magistrate's flaws apparent, but ultimately acceptable because they are human, perhaps, and because they are contextualized in a wider pattern of self-awareness and hopeful humility.
"There girl lies in my bed, but there is no good reason why it should be a bed. I behave in some ways like a lover -- I undress her, I bathe her, I stroke her, I sleep beside her -- but I might equally well tie her to a chair and beat her, it would be no less intimate."
The magistrate is never confident in the morality or correctness of his actions. Rather, he experiences an almost continuous angst as he grapples with questions of ethics and morality and undertakes the larger pursuit of honest self-knowledge.
This tendency in the magistrate effectively treats his flaws as part of his attempt at achieving his goal of coming to an honest view of himself.
At the same time, the magistrate's flaws often demonstrate the weaknesses of his character that accompany his inability to actually achieve his goal of self-knowledge. Seeking basic animal comforts, with his full belly and his position in the town, the magistrate insulates himself from the harsh realities that characterize the empire's relationship to the natives on the frontier.
The magistrate's efforts to understand himself can be seen as a stand-in or a metaphor for an effort to understand this relationship between the empire and the peoples whose territory it now occupies. We see indications of this connection in the magistrate's hobby of collecting the marked slips that he finds buried in the desert.
He is engaged in a project of deciphering, which becomes a leitmotif associated with the magistrate. This term ("deciphering") applies perfectly to his obscure hobby, as he attempts to read literal ciphers. It also applies nicely to his repeated attempts to understand his dreams and to understand the barbarian girl. The dream and the girl are also ciphers that the magistrate wants to decode, to understand. In order to honestly understand his own place in the world, the magistrate must understand the relationship between the empire and history and between the empire and the barbarians.
"He associates one of the children with the barbarian girl. In waking life, he finds the barbarian girl impenetrable—a blank surface—and wonders if that is what the torturers felt as well. Through the girl, he begins to discover his complicity with the torturers" (enotes).
In his weakness for carnal pleasure, the magistrate chooses momentary oblivion/ignorance over knowledge. He realizes quite consciously that his lapses into oblivion stand against his larger aims. By recognizing his limitations, the magistrate makes his most potent commentary on the empire, which never questions its own righteousness.
"In my opposition, there is nothing heroic -- let me not for an instant forget that.