Suffer the Little Children (Commissario Brunetti #16) by Donna Leon. 2007. Softcover.

When Commissario Brunetti is summoned in the middle of the night to the hospital bed of a senior pediatrician, he is confronted with more questions than answers. Three men—a young Carabiniere captain and two privates from out of town—have burst into the doctor's apartment in the middle of the night, attacked him and taken away his eighteenth-month old baby boy. What could have motivated an assault by the forces of the state so violent it has left the doctor mute? Who would have authorized such an alarming operation? At the same time, Brunetti’s colleague Inspector Vianello discovers a money-making scam between pharmacists and doctors in the city. But it appears as if one of the pharmacists is after more than money. Donna Leon's new novel is as subtle and fascinating as ever, set in a beautifully-realized Venice, a glorious city seething with small-town vice.