Detective Drake inspected a museum break-in. The thief had bypassed an advanced retinal scanner by holding a high-definition photograph of the curator's eye up to the lens. Drake shook his head and told the museum director that an inside job was impossible, but the photograph itself proved the thief was an amateur. Why?
A retinal scanner requires a living pulse
A retinal scanner shines a light into the eye to read the blood vessel patterns on the retina, which requires a live, dilated blood flow. A static photograph lacks a pulse, blood flow, and the subtle microscopic movements of a living eye, making it useless on any modern scanner.
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: Medium. More like this: Detective riddles with answers or try Truth & Lie Island for a different kind of puzzle.
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