More than two years later, on 15th September 1934, the police had the breakthrough they needed: a petrol station manager, Walter Lyle, suspicious of an old-fashioned gold-backed ten dollar note he received in payment for petrol, wrote down the license plate number of the purchaser. It was traced back to a 35 year-old German immigrant, a carpenter called Richard Bruno Hauptmann, who lived in the Bronx.
Hauptmann was discovered to have entered the United States illegally in 1923, and had a criminal record for robbery, in one case having used a ladder to commit the crime. Significantly for the police, he had suddenly given up his carpentering trade around May 1932, and become a stock investor.
Hauptmann was found to have another Lindbergh note on his person, when he was arrested outside his home on 19th September 1934. His home was practically dismantled in the subsequent search, and over $14,000 of the ransom money was found hidden in the wall joists of a garage, which Hauptmann had built himself. In addition, a missing rafter in Hauptmann’s attic exactly matched an upright strut in the kidnap ladder.
Under intense interrogation, Hauptmann maintained that a former business partner, Isador Fisch, had given the money to him, before he departed for Germany in December 1933, although, as Fisch had died of tuberculosis in Germany in March 1934, Hauptmann could not provide corroboration of his account. He was required to provide a sample of his handwriting, which experts concluded matched the handwriting in the ransom note.