Arthur Koehler

Arthur Koehler was a U.S. federal expert wood detective who was important in the investigation of the Lindbergh kidnapping. He carefully examined the ladder which had been used by the abductor of Charles Lindbergh, Jr., aged twenty months, and traced the ladder to a company in McCormick, South Carolina. Koehler, from there, traced the wood of the ladder to a Bronx lumber yard.

In the trial of Bruno Hauptmann, Koehler brought out his evidence which helped to indict Hauptmann of the kidnapping and sent Hauptmann to the electric chair. After it was discovered that plank had disappeared from Hauptmann's attic, Koehler brought out his evidence: the wood he traced to Hauptmann. He proved, by fitting the two pieces together, that the attic board matched with the ladder rail used by the kidnapper, giving evidence that Hauptmann built the ladder. His evidence brought to the jury's decision to execute Bruno Hauptmann.