Personally I think The Partner by John Grisham is his best. In his later works he tries to extend his style from the legal thriller genre, and I don't think it has been very successful, although the Grishamists would buy whatever he produces. I haven't read his The Appeal.
Based on what you like, I strongly recommend Ken Follet, starting from his most enjoyable Eye of Needle. You can also pay attention to Jeffrey Archer, starting from his best Kane and Abel. Scott Turow's legal thrillers are also very readable.
Based on what you like, I strongly recommend Ken Follet, starting from his most enjoyable Eye of Needle. You can also pay attention to Jeffrey Archer, starting from his best Kane and Abel. Scott Turow's legal thrillers are also very readable.