This seminar will explore various ways in which the powers of Congress, the Executive, and the federal courts are informed by historical practice. Some of the class sessions will focus on general theoretical questions, such as the relationship between governmental practice and law, the extent to which particular constitutional theories are receptive to practice-based argumentation, and the idea of non-judicial precedent. Other sessions will address specific constitutional questions, such as the war powers of Congress and the President, the validity of executive agreements, and the scope of the President's removal power. The seminar will also be interdisciplinary in that it will explore insights from political science about how the branches of the U.S. government actually interact in practice. Columbia Law School will be offering a similar seminar in the fall, and students at the two schools will be encouraged to interact through online postings about the readings. All students will be required to complete a research paper by the end of the semester. Grades will be based on the paper, the online postings, and in-class participation.