A crime novel that's not really about the crime: The Round House

Louise Erdrich;s The Round House is developing as a crime novel, something of a mystery (we don't know yet who committed the vicious rape and assault on narrator Joe's mother, so it's a mystery in that sense) but the novel is not so much, I think, about solving a crime as about delineating a character and depicting a community, in this novel as in all (?) of Erdrich's fiction a North Dakota reservation - yesterday I mentioned Blackfoot, but from last night's reading see that it could be Chippewa or Ojibwe, not sure - there may be a lot of intermarriage among these tribes in any case so not sure the tribal affiliation matters greatly. Narrator Joe is an Indian teenager, good kid, but occasionally into trouble - smoking and drinking and some illegal cruising, nothing too serious; his mother, who's in some kind of tribal administrative position, is attacked and clearly suffers from trauma - pretty much stops eating and won't allow physical contact with her husband, Joe's father, who's a tribal-court judge. Joe's mission is to solve the mystery of his mother's attack and thereby, he hope, heal the family wound and bring his parents back together, as they had been - a very sweet and loving relationship, by all accounts. Joe and his friends go off to the Round House, a kind of prayer house, seldom used, and the locale of the crime; they find a lot of trash around, all of it potential evidence, including a gas canister that the perp probably used in his attack and tried to hide (in the lake). It's not surprising that the police didn't find this; that's part of the message of the novel, the disposable nature of the Indians and the indifference of the white culture to crimes committed on the rez. There seem to be two possible sources for the act: vengeance because of case that had come before Joe's father, which leads them both to pour through his case files, or some attack on the tribe acted out through Joe's mother - mysteriously, the attack occurred after a call drew her into her office on a Sunday to check for a file. Toward the end of the opening section, in Erdrich fashion, Joe sees a ghost outside his house, watching, and Joe's father, though generally quite the rationalist, assures him casually that the ghost is real - but who is it and why it he staring at Joe's family's house?