Who is Esme Tavarez, a.k.a. Angela Martinez

Esme Tavarez is a young woman in San Fernando who went missing years before the events of the novel. If is presumed that she has been urdered. Bosch is investigating her case on the day when he is interrupted with the news of both the pharmacy murders and the potential legal case against him. After both of those cases have resolved, Bosch is surprised to be contacted by Tavarez, who reveals that she had changed her name to Angela Martinez and moved to Salt Lake City when she had disappeared. Bosch concludes that she is selfish because she left her young infant child behind and effectively wasted much of the police's resources.