Book excerpt: "Whose law must I obey? This question is so basic to our legal obligations that it ought to be easy. Specifically, a person considering an action ought to be able to answer this question by the use of law-like rules. This ought to be particularly true of criminal law, which will be the principal focus of this book. Actually, this question is partially unanswerable in the world as it exists today. Whether by accident or design, the current structure and content of law-national and international-sometimes prevents persons (natural or juridical) from being able to answer the question fully at the time of action"--