University of Chicago law professor David Strauss is a former colleague of Supreme Court nominee Elena Kagan. He considers her someone who comes to the bench without a personal agenda. That's important to Strauss, a constitutional law expert who has argued before the Supreme Court many times. He sat down with us to talk more about the role of the Constitution and the highest court. In his new book The Living Constitution, Strauss takes up the role of constitutional interpretation in lawmaking.