The Scarecrow, by Michael Connelly

Jack McEvoy is a journalist, on his last legs at the L.A. Times, who has just written a brief article about the arrest of a gangbanger, Alonzo Winslow, for torturing and murdering a  young woman and stuffing her body in the trunk of her car. Alonzo's grandmother calls McEvoy to protest her boy's innocence, and he decides to look into the case a little deeper, thinking that perhaps he can write a gripping story about how a young person reaches the point where they can commit such a horrible crime, his last big hurrah before he leaves the paper in two weeks.
As he digs deeper, however, he discovers that there has been another murder, commited in Las Vegas, and that the method of disposing of the body bears eerie similarities to the Winslow case. Could the boy, in fact, be innocent, framed for the murder by a cold and calculating serial killer?
McEvoy flies to Las Vegas to talk with the lawyer for the man who has been convicted and put in prison for this other murder, and things start to get hairy. He calls in Rachel Walling, an FBI agent whom he has worked with on a previous case (also a previous Connelly novel, The Poet), and together the two begin to chase down the killer, even as the killer begins to chase them.
Connelly does a nice job in this book of creating suspense, and though we know all along, from vignettes from the killer's point of view, who dunnit, there's still a few surprises in store.