The jeweler claimed his safe was robbed while he slept upstairs. The heavy steel door was swung wide open, and all the diamond rings were gone. Detective Briggs inspected the floor and found a thick layer of undisturbed dust right across the doorway threshold where the heavy door would have swung. Briggs arrested the jeweler for insurance fraud. Why?
The door swung open over the dust
If the heavy steel door swung open, it would have disturbed the thick layer of dust across the threshold. Since the dust was completely undisturbed, the door hadn't actually been opened in that direction, proving the robbery was faked.
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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