John Paul Stevens was born on April 20, 1920. He opened his eyes in the early years of “the American century,” when many in the young nation, right or wrong, looked ahead to a future imagined as an uninterrupted parade of national growth. He closed them Tuesday at his home in Fort Lauderdale, Florida, at a time when the future seems far more foreboding.

After the Depression and the law nearly destroyed his family, Stevens attended the University of Chicago. He joined the Navy on the day before the Japanese attack on Pearl Harbor; his work compiling and decoding Japanese radio transmissions helped guide the Navy planes that shot down and killed Admiral Isoroku Yamamoto, the architect of the attack, a year and a half later. (Stevens later received a Bronze Star for his service.) After the war, he studied law at Northwestern University and clerked for Supreme Court Justice Wiley Rutledge; but he learned his craft not in government service but as a private lawyer in Chicago. Though his specialty was antitrust, he took time out of his career to provide counsel for an investigating commission that uncovered corruption on the Illinois appellate bench, and later staffed a congressional investigation into antitrust aspects of professional baseball.

His ascent to the bench flowed directly from the traumatic collapse of Richard Nixon’s presidency. Nixon’s successor, Gerald Ford, sought to provide a unifying nomination after the sharp divisions of the Watergate era. He succeeded—Stevens won unanimous approval from a Democratic-majority Senate. Ford did not win election the next year; he later said, “I am prepared to allow history’s judgment of my term in office to rest—if necessary, exclusively—on my nomination 30 years ago of Justice John Paul Stevens to the U.S. Supreme Court.”

Stevens joined the Court in 1975 as a moderately conservative justice on a moderately liberal Court; though his views in some areas—for example, the death penalty and race-based affirmative action—moved somewhat left, he still departed the Court in 2010 as a moderately conservative justice. He always believed that government should have some power to restrict “indecent” speech, whether in granting radio licenses or allowing “adult” establishments in local communities, and he was adamant that the First Amendment need not protect those who burned the American flag as a political gesture. So intense was the Court’s rightward shift, however, that by the end of his career, Stevens was seen as a liberal, and operated for 16 years as the field marshal of the Court’s left side.

His majority opinions are important—especially his two decisions, Rasul v. Bush and Hamdan v. Rumsfeld, that required the executive branch to give legal protections to foreign detainees in the years after the September 11 attacks. But for the near future, it is the dissents that will serve as a springboard for criticizing Donald Trump–era jurisprudence.