In "The Purloined Letter," there is a striking difference in how the prefect of the Persian police handles the missing letter compared to Dupin. The focus of the police department is a desperate search of the premises where the queen's letter has disappeared. The prefect's strategy is simple: find the letter. He seems to know already that a disgruntled minister has taken the item but spends no time exploring motive, opportunity, or criminal psychology.

After a month of searching with no letter to be found, the prefect comes to see Auguste Dupin and is shocked to discover he has the letter in question. However, before Dupin hands over the coveted item, he inquires how much the prefect would pay for such a break in the case. After acquiring the large sum, Dupin explains the logic he used to uncover the stolen letter.

Dupin uses deduction skills, which the character Sherlock Holmes would later popularize, to determine that the minister is clever enough to know that a thorough search would follow the theft. Therefore, as Dupin correctly deduces, the minister placed the letter in plain sight to avoid detection. Dupin quickly discovered it, replaced it with a facsimile, and held onto the valuable note until the prefect appeared in the story again, this time more desperate to find the item than ever before.

Dupin demonstrates that true crime-solving requires logic and keen deduction skills that all good detectives should possess.