Constance is not a good person but what happened to her was an extreme miscarriage of justice. The fact that she had an advocate through it all, to the end of his own life, and even beyond was a rare gift and it kept the book interesting. 

While the plot is somewhat predictable, it is based on a true story so that cannot much be blamed on the author. I found myself very interested in the trial and what was going to happen. 100% a good read for lovers of historical dramas.