A stamp collector was found dead in his study, surrounded by hundreds of rare envelopes. His tea was poisoned. A magnifying glass lay on the desk. The detective noticed that one specific envelope on the desk had a modern barcode printed on it, even though the stamp and postmark were dated 1895. The detective immediately suspected the victim's nephew. Why?
Barcodes did not exist in 1895.
Modern barcodes were invented in the 20th century. An envelope bearing a barcode could not possibly be a genuine antique from 1895; it was a modern forgery planted by the nephew.
About this riddle
Detective riddles are tiny mysteries. Look for the detail in the story that does not fit; it is usually the clue that solves the case.
Difficulty: Easy. More like this: Detective riddles with answers or try Truth & Lie Island for a different kind of puzzle.
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