Shiloh (by Phyllis Reynolds Naylor)

At first, the situation in SHILOH seems clear: Judd is mean, and Marty is heroically trying to protect a defenseless dog. But things soon become less clear-cut, and Marty's actions inadvertently cause Shiloh to suffer far more seriously than he did at Judd's hands. And keeping Shiloh away from Judd seems to drag Marty increasingly into behavior that he knows is wrong. He slides rapidly down the slope of the ends justifying the means, which are increasingly dishonest.

Finally, Marty's choices narrow to trying to decide on the lesser of evils, rather than choosing what is clearly right, and in the end the biggest lesson the book seems to teach is that nothing is as simple as it seems. This nerve-wracking story, which challenges readers to think for themselves, refuses to make things easy.