Hanging on the wall of his Harvard Law School office, Professor Richard Lazarus has a framed copy of the 2007 Massachusetts v. EPA ruling signed by Justice John Paul Stevens.

It is a symbol of the significance of the case for Lazarus, who has written the book “The Rule of Five: Making Climate Change History at the Supreme Court,” which tells the inside story of the landmark environmental case.

The Harvard Gazette sat down with Lazarus, a Supreme Court advocate and the Howard and Katherine Aibel Professor of Law, before the coronavirus quarantine to talk about his book, his passion for environmental law, and the legal strategy behind the environmentalists’ victory.