What is the author's style in The Third Policeman by Flann O'Brien?

The Third Policeman is told from the first person perspective of an unnamed narrator. The narrator goes through a very subjective experience: death. Everything in the afterlife refers back to the narrator's experiences in life and the narrator's defining sin, the murder of Mathers. However, the narrator does not seem to make the connections between what is happening and his own life. Instead, he tends to make connections between what happens and de Selby's writings. The narrative voice, in fact, takes on two characters during the novel. When the narrator writes about de Selby, he writes authoritatively and academically, but when he writes about his experiences, he shows a naive and even thoughtless approach to his surroundings.