It was a single note that reached Angélica Mendoza de Ascarza after her son Arquímedes was taken from her home by soldiers in Peru’s military. In faint cursive on a scrap of deeply creased brown paper, he wrote that he was being held at an army barracks and asked her to find a lawyer and money and any way possible to get him to a trial.

History matters at the U.S. Supreme Court, where most justices either embrace or occasionally rely on a form of interpretation called “originalism,” which holds that the original meaning of the Constitution should be sought, and relied on, to decide cases.