The 2 stars are...1: for Jensen Ackles, 2: for the scenery.
Absolutely ridiculous plot development, no character development, just centered around two what would be really unprofessional, downright negligible at their job PI's/cop. The first season had some potential - the good thing being the actor who plays Ronald, an actual attempt at character exploration/development. Too bad they only use Ryan Philippe as a tactic to get you to watch the show. His part is short and completely irrelevant.
The second season is just painful and ridiculous. This show clearly did not do any background into legal procedure. The lead character who is supposed to be a trained cop is so emotionally fraught over a guy, who is an undercover cop, that she practically blows his cover on several occasions. That's only the tip of the ice-berg of the culmination of things that are wrong with this series.
I've watched to season 3 because I'm a Jensen Ackles fan. I think Ackles female following is exactly why they have put him in the series, that's not to take from him as an actor. Producers know his following and are banking on his charisma in the role to bring in the viewership. He does bring his usual charm to the screen but it's not enough when everything else about the series is such a mess.
I'm sure the books are probably a great read but this series does not portray that.