Well, that was embarrassing! Leon, we know, is not the most subtle of writers when it comes to unwinding a theme and, to be fair, she has to balance her political points with the frame of a murder mystery and the Brunetti formula of Venetian colour + Brunetti family charm + Guido milking all his contacts + Signorina Elettra doing her techie thing + Italian corruption and Mafia crime.
All the same, this seems particularly tone-deaf when it comes to dealing with the topic of race and immigrants: while Guido and Paola express their horror at Chiara's dismissal of an immigrant death, they also never stop 'othering' the 'Senegalese', making much of their blackness, their tribal markings, and everything that keeps them alien from Italians/Europeans, despite many people agreeing that they're polite, quiet and speak good Italian, albeit with an accent. Because yes, they turn out not to be from Senegal at all, but from Angola, a former Portuguese colony - but, then, as many people imply, including Guido, Africa is Africa and the book isn't interested in the numerous countries and cultures which make up that vast continent.
Throughout, the murdered man is just 'the black man' - nameless, dead, silenced - and it's rare that any of his companions actually speak, keeping them at arms distance and 'different' from both the characters and reader.
On top of the clumsy race narrative (and I'm guessing Leon thought she was being empathetic and highlighting a problem in Italy), Guido - that well-informed and well-read man - doesn't see the clues to this mystery which are right in front of his eyes so that the reader has guessed the plot well ahead of him. Oh, and there's a particularly obvious little scene where Chiara brings an Iranian girl home for lunch just so we can be reassured that the Brunettis can welcome 'foreigners' into their midst.
If this had been written in the 1970s-80s, it might have been indicative of social mores - but for something published in 2005, this feels dated and uncomfortable.