American Constitutional Law, Volume I provides a comprehensive account of the nation's defining document, examining how its provisions were originally understood by those who drafted and ratified it, and how they have since been interpreted by the Supreme Court, Congress, the President, lower federal courts, and state judiciaries. Clear and accessible chapter introductions and a careful balance between classic and recent cases provide students with a sense of how the law has been understood and construed over the years.

The 12th Edition has been fully revised to include several new cases, including many involving President Donald J. Trump. Chapter 7, Federalism, has been revised to add several cases, previously in Volume II, pertaining to voting and elections. A new companion website, https://americanconlaw.com/, offers access to primary documents and every case that formerly appeared in American Constitutional Law.