A mafia novel set in Sicity that's a great example of Italian noir

Started reading Leonardo Sciascia's The Day of the Owl (1961), a brave novel that takes on the mafia in home turf, i.e., Sicily. It's easy to dismiss this as "just" a crime novel, but it seems, at least from the first 50 pages of so, that Sciascia is using a crime story to depict a whole society and its corruption, complicity in corruption, and reign of terror. The central characters is a police captain, from the north of Italy (Emilia), assigned to Sicily, who takes it on himself to conduct a serious investigation of a shooting in a public square, obviously a mob hit, the kind of thing that nobody else had ever looked at - maybe an outsider can get at the truth. We'll see. The first few chapters are grimly hilarious: the man is shot as he's running to catch a bus leaving the nearly empty square at 6 in the morning; there are a out 50 people on the bus, plus a street vendor at the bus stop. After the man is shot dead and the police arrive, all of the passengers somehow manage to "disappear." They track down the vendor and, after assuring him that they're not questioning his vendor's license of anything of the sort, they say they just want to ask him about the shooting. To which he says: Somebody was shot? So we see what the captain is up against. There's an interpolated chapter in which two men in Rome (I think) engage in discussion about the unions in Sicily and the communists and the "partisans" - these affiliations elude me, but they may become more clear as the plot progresses. The story has potential I would think to be a good, if by now pretty familiar, movie or TV show - but LS's writing lifts the story up to another level: His dialogue is smart, the captain is especially  intelligent and perceptive (he calls in a group of men in a construction firm that may have been a target of the shooting and has each man sign a register - we learn later this was to get handwriting samples to match against and letter he received from an anonymous tipster, as just one example), and he efficiently sketches in a sense of an entire community: we understand the secrets and lies that were a part of living in Sicily in that era, the fear of not knowing who's allied with whom, the petty and not so petty corruption - a really good example of Italian noir.