For me the story played out quite well, dropping a little more information at a time. I can understand Angel's initial uncertainty over how many shots she had fired, and her confusion as the story progressed, especially as evidence disappeared. I can also understand - to a degree - her hesitancy over Callen's intentions as she was not sure who was on her side and who wasn't. Sure, she was incredibly naive, even stupid at times. She knew that everyone would have told her not to go to the funeral, but she decided not to tell them and went anyway, and on more than one occasion she tried investigating things she had no business getting into. I kept thinking - she is a uniformed officer, not a detective, what on earth is she doing? I also felt that her fears that her father might have had something to do with it were very plausible, if only because it wasn't easily explained, and therefore kept her in a position where she was on the back foot because she was worried about what she might uncover. It soon became obvious that the offender had to be a police officer but the author was very good at casting suspicion on all of them at different times making it almost impossible to guess who, until she was ready to reveal the identity to us.
Not brilliant, but a very pleasurable way to pass some time.