This is the eighth one of the Commissario Brunetti stories, and I realized that, when I went back to them some time last year, I couldn't find the very first one for Kindle. So, I went to check - and it is now available for $.99 - love those 99 cent books - so I got it. I don't believe I've ever read it, but I am not going to start from the beginning of the series again!
The last couple of these have seemed to focus more on Brunetti's relationship with his wife, Paola. She is a professor of English literature and the daughter of traditional Venetian nobility. We are occasionally reminded that Brunetti has a law degree in addition to being a chief detective. This time their relationship is put to the test when Paola decides to "do something" about a travel agent whose stock in trade is "sex tours" to third world countries where those with tastes unacceptable in western society can buy young children. The something she does is to throw a rock through the window of the place and get herself arrested.
This is fairly embarrassing for Brunetti, and gets him put on administrative leave by his incompetent supervisor, Vice Questore Patta, until the owner of the travel agency is murdered when Brunetti is called back to take charge of the case. Explaining the title would be a total spoiler - and that's all the hint you are getting.
An early one of these involved the American army base at Vicenza where daughter #2 was born, and the Brunetti's daughter is named Chiara - sufficient reason for enjoying the series. This one even had an American cop show style attempt to apprehend a suspect with doors being knocked down and shooting and everything.