Britannica Educational Publishing 
U.S. Constitution and Constitutional Law [PDF ebook] 

Although one of the shortest written constitutions in the world, the U.S. Constitution, designed to embody the rights, laws, and guiding principles of a diverse and ever-changing populace, remains an enduring document. Since its ratification in 1787, the Constitution has been applied to a broad range of legal and political questions and, while often the subject of much debate, continues to serve as a stalwart reminder of the country’s social and legal strides. This detailed volume breaks down each section of the Constitution and its amendments, also providing a concise overview of the field of constitutional law as it is applied around the world and in various forms of government.