Falling on Deaf Ears asks, how reliable are ear-witnesses? Not very:
Bruno Richard Hauptmann was executed in Trenton, N.J., in April 1936, for kidnapping and murdering the young son of the famous aviator Charles Lindbergh. The most dramatic moment in Hauptmann’s closely watched trial came when Lindbergh identified Hauptmann’s voice as that of his son’s kidnapper. “The minute Lindbergh pointed his finger at Hauptmann, the trial was over,” said Hauptmann’s lawyer after the conviction. “Jesus Christ himself said he was convinced this was the man who killed his son. Who was anybody to doubt him or deny him justice?”
Lindbergh had heard the voice of his son’s kidnapper three years earlier. Still hoping to get the child back alive, Lindbergh had accompanied Dr. John Condon to St. Raymond’s Cemetery in the Bronx to deliver ransom money. Condon handed off $50,000 in marked gold certificates, while Lindbergh waited nearly 100 yards away in a car. Out of the darkness came the words, “Hey, doctor! Over here, over here.”
Twenty-nine months after the encounter in the cemetery, in September 1934, Lindbergh told a Bronx grand jury that “it would be very difficult to sit here and say that I could pick a man by that voice.” Undeterred, the district attorney asked Lindbergh later that day: “Would you like to see the man who kidnapped your son?” The next morning, while Lindbergh sat in the back of the D.A.’s office among a group of detectives, Hauptmann was brought in and asked to repeat the words, “Hey, doctor. Here, doctor, over here.” Lindbergh told the prosecutor that he recognized the voice as that of the kidnapper, and he testified under oath at the trial that Hauptmann was the man he had heard in the cemetery.
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One year after Hauptmann’s execution, Frances McGehee, a psychology professor at the University of Illinois, had students listen to a person read a 56-word passage from behind a screen. The students were then tested at various times to see whether they could pick the reader out from a group of five voices. They did so with 83 percent accuracy the next day. Three weeks later, however, their success rate had declined dramatically to 51 percent. Five months later they were down to a dismal 13 percent accuracy rate — well below chance.