The following is an essay for our thirty-day series on Justice Stevens, by Chicago Tribune editor and columnist Bill Barnhart.  Barnhart is the author of a forthcoming biography on the justice, John Paul Stevens: An Independent Life (Northern Illinois University Press, 2010).

Former Chief Justice William H. Rehnquist, quoting an unnamed predecessor, said that being nominated to the Supreme Court was largely a matter of standing at the right spot "when the bus went by." Certainly, political, geographical, sexual and even religious characteristics often have determined who is standing at the right spot at the right time. For that reason, the actual qualifications "“ or lack thereof "“ of a Supreme Court candidate frequently are overlooked.

Judge John Paul Stevens of the U.S. Court of Appeals for the Seventh Circuit in Chicago was in the right spot for two reasons in 1975 when Justice William O. Douglas retired. First, Stevens was known and respected by President Gerald R. Ford's attorney general, Edward H. Levi (Stevens had taught Levi's University of Chicago law school class in monopoly law). Second, he had no political resume and was unknown to the public, facts which fit perfectly with Ford's nomination strategy.

Stevens's legitimate qualifications received perfunctory review in the Senate confirmation process, which took less than three weeks from nomination to swearing-in.  One crucial factor in Stevens's background "“ his top-secret work for the U.S. Navy in Pearl Harbor during World War II "“ was barely mentioned. Yet in my opinion, Stevens's work as a twenty-something communications officer interpreting Japanese radio signals was as important to his success as an associate justice as his law school studies, his clerkship for Justice Wiley B. Rutledge, his work as a corporate lawyer, and his service on the federal appeals bench in his hometown.

John Stevens was recruited into naval intelligence work during his senior year by one of the deans of the University of Chicago undergraduate college. Leon Perdue Smith, Jr., a suave and handsome native of Georgia who had received his Ph.D. in French literature at the university in 1930, was what spy novelist John Le Carre calls a talent spotter. "He was the undercover guy," Stevens told me and my research associate, Gene Schlickman.  Smith, an expert on interpreting ancient and rare literary manuscripts, had been a code-breaker for the navy in World War I.

Mathematicians typically gravitate to the art of breaking codes and interpreting secret messages. But, as English literature major Stevens discovered, philology and cryptology have much in common. Smith regaled Stevens with the challenging work of "solving" complicated signal patterns. He conveyed a scholar's thrill of the hunt. With Smith's encouragement, Stevens enrolled in a program that was not on the University of Chicago's course list — the navy's restricted correspondence course in cryptography.

Stints in America's secret services in World War II often led to successful careers in the public and private sectors. Justice Lewis F. Powell, Jr., with whom Stevens served for most of Powell's fifteen-year tenure on the Supreme Court, had been a senior officer in the army's communications intelligence operation in Europe, directing relations between British and American cryptanalysts. Stevens, by contrast, was a junior officer trained at the navy's headquarters in Washington and deployed in early 1943 for unglamorous duty at an intelligence outpost called Station Hypo (H, as in Hawaii) in Pearl Harbor.  After Japan's attack on December 7, 1941, navy brass in Washington considered Station Hypo to be a career dead-end and, worse, a whipping boy for the U.S. Navy's failure to warn President Franklin D. Roosevelt of the Pearl Harbor attack.

"I was conscious of it," Stevens recalled. "When I arrived there, I was sort of a newcomer from the hostile territory. There was definitely friction at that time."  The work was being performed around the clock in the cramped, dank and heavily guarded basement of a navy administration building. (In the 1976 movie Midway, the head of the unit was portrayed by a smart but frenetic Hal Holbrook.) After the Pearl Harbor attack, military decorum was abandoned throughout much of Pearl Harbor, nowhere more so than in the basement. Formerly spit-and-polish navy band musicians from the battleship California, which was sunk in the December 7 attack, found themselves reassigned to employ their musical skills in interpreting enemy radio signals in the top-secret basement.

"When I arrived at Pearl, the (Hypo) unit"”then known as FRUPAC [Fleet Radio Unit, Pacific]"”was still in the basement," Stevens recalled. He joined an "exceptionally fine bunch of men"”both officers and enlisted"”who worked in the unit. . . .  Many of them were musicians, having been members of the band of a battle wagon.  I learned what really lousy coffee tastes like, and eventually came to like it," he said.

Contrary to most biographical sketches of Justice Stevens, he was not a code-breaker. The Japanese radio code had been broken before the war "“ a fact that made his work of applying the code to radio signals super-secret. His assignment was called traffic analysis "“ unraveling the source and destination of radio messages as a way of determining movements of Japanese ships.

Despite the intellectual appeal of the work, choosing communications intelligence duty was hardly a smart career path in the navy, especially in wartime. Since before World War I, old-timers in all military branches had regarded tapping an enemy's messages as ungentlemanly. Indeed, the Federal Communications Act of 1934 prohibited the interception of radio messages from foreign countries. More important, junior officers were expected to serve time on ships at sea during combat in order to advance in the ranks. Few graduates of the U.S. Naval Academy at Annapolis aspired to land-based assignments in communications intelligence. For one thing, men steeped in enemy codes typically were kept off ships for fear that they would be captured and forced to reveal secrets.

The tension between Washington and Pearl Harbor reflected itself in professional rivalry, as both units struggled to interpret radio signals quickly and accurately. The key to being first in solving a puzzle was teamwork, recalled Robert W. Turner, one of Stevens's fellow Station Hypo junior officers. Officers and enlisted men performed identical operations on hundreds of intercepted messages, twenty-four hours a day, seven days a week. Deviations from agreed procedures destroyed the uniformity vital to uncovering statistical probabilities in signal patterns. On the other hand, the work required solitary, creative thinking in detecting novel patterns.

"We were not being shot at, nor did we shoot at anyone, so our off-time diversions would have been idyllic to much of the military. However, radio intelligence and traffic analysis was a key part of it, became obsessive, and people worked inordinate hours because they just couldn't drop an idea before running it to the end available to them." said Turner. He remembered the near-obsession of the work: "You had all the resources available to you; you just needed the energy and the curiosity to follow up on it. Given John's proclivity, you can get real excited about this stuff. It becomes very absorbing. You have to figure out these puzzles."

Stevens recalled that he and several enlisted men "worked together around the clock for three or four days to break a new daily-changing call sign encipherment system, with the familiar weather intercepts providing the raw material for the reconstruction of what turned out to be a very simple strip cipher," Stevens said. "I remember the incident with particular pleasure because several days after we had the whole thing figured out, we were still getting messages from Washington advising us that they had received few values [plain text interpretations]."  He smiled when he told us, "They were so far behind it was almost embarrassing."

Daily typewritten reports supervised by Stevens, Turner, and other watch officers were delivered to Commander Edwin T. Layton, the liaison between the navy's communications intelligence operation in Hawaii and Admiral Chester W. Nimitz, commander of the U.S. Pacific fleet. Many of the typewritten reports during Stevens's tenure contain handwritten notations in pencil and the initials "JPS" now so familiar to Supreme Court clerks, scholars and litigants.

Anyone familiar with the speed, incisiveness, and confidentiality "“ not to mention the consequence — of Stevens's work on the Supreme Court can see the direct parallel to his work as a young navy officer at Station Hypo.

Two days before his twenty-third birthday, Stevens reviewed a message that stayed with him the rest of his life. "I happened to be on duty when the message came in advising that our pilots had bagged a peacock and two sparrows," Stevens recalled. The incident went down in naval history as the Yamamoto shoot-down. Revered in Japan and respected among U.S. Navy veterans, even after the war began, Admiral Isoroku Yamamoto (the peacock) commanded the Japanese combined fleet. Although he had opposed his nation's plan to wage war on the United States, he was the architect and leader of the Pearl Harbor attack and Japan's war in the Pacific. Commander Layton, who spoke Japanese and had served in Japan before the war, knew him well.

On April 14, 1943, FRUPAC watch officers reported fragments of a message dated April 13 that they believed disclosed a plan by Yamamoto, "the Commander-in-Chief," to fly on April 18 from his headquarters at a former Australian naval base at Rabaul on New Britain Island to visit Japanese air bases a few hours away in and around Bougainville Island in the northern Solomon Sea. After quick review, Admiral Nimitz authorized a mission to shoot down Yamamoto's plane and an accompanying plane (the sparrows).

The Yamamoto shoot-down marked the beginning of the end of Japan's military offensive. But several issues presented themselves in the wake of the incident: Yamamoto was a voice of moderation in Japan who might have helped convince his superiors to end the war before the U.S. atomic bomb attack. It was unclear whom the allies would face as his successor. U.S. intelligence officials also worried that a successful targeting of Yamamoto might reveal the extent of U.S. penetration of Japanese radio codes. A deeper question concerned the ethics of targeting an individual for assassination in wartime. "I had mixed feelings at the time, because, on the one hand, it was an important and successful operation but, on the other hand, it was a deliberate elimination of a specific individual rather than a nameless enemy," Stevens recalled.

Still, Stevens's characterizations of his wartime experience in Hawaii reflect a sense of his unit's independent, if unheralded, spirit. "Despite occasional problems with garbles, traffic analysis . . . made significant contributions to our understanding of what the enemy was up to," he recalled in a 1983 speech to fellow cryptanalysts. "Altogether, what I saw at Pearl convinced me that the value of the work done there"”both before the war started and while it was being fought"”was seriously underestimated by the folks in Washington."

Posted in 30 Days of Stevens, Special Features