Senator Pierce (Mitchell Ryan) describes his nephew as "lean and hungry," a reference to Shakespeare's Julius Caesar: "Let me have men about me that are fat, sleek-headed men and such as sleep a-nights. Yond Cassius has a lean and hungry look, he thinks too much; such men are dangerous."
Ashland says "let us sit upon the ground and tell sad stories of the death of kings", a quote from Shakespeare's Richard II.
The case Mulready and Lang are speaking of is U.S. v Lopez, a landmark Supreme Court case in which the Supreme Court ended 50 years of precedents allowing Congress to federally mandate certain legal standards (including civil rights and federal gun control laws) based on a very liberal interpretation of the Commerce Clause (Article 1, Section 8. Clause 3) of the U.S. Constitution.
President Bartlet (Martin Sheen) has nominated 3 Supreme Court justices, including Roberto Mendoza (Edward James Olmos) in "The Short List" from the first season, and Christopher Mulready (William Fichtner) and Evelyn Baker Lang (Glenn Close) in this episode.