In November 1964, the U.S. Government Printing Office released what might be the most specialized reference set ever published. At 18,000 pages, it rivaled The Oxford English Dictionary and the Encyclopedia Britannica in terms of shelf inches. But while those efforts attempted to cover the history of the English language and the sweep of human knowledge, respectively, all 26 volumes of Hearings Before the President’s Commission on the Assassination of President Kennedy were devoted to six seconds, give or take.

Two months earlier, the Warren Commission had delivered its final report, pronouncing Lee Harvey Oswald guilty. Commissioner Richard Russell, the chairman of the Senate Armed Services Committee, felt they should also air the evidentiary record to show how they’d reached their verdict. His fellow commissioner Allen Dulles thought it was a waste of money. “Nobody reads,” the former C.I.A. director said. In the end, Dulles was outvoted, and Congress approved the necessary funds. The $1 million cost was justified as a worthy investment in public trust, one that would reap dividends for years to come.