A rare coin collector was found murdered in his vault. The combination lock was untouched. Inside, a single flashlight was left shining on an empty velvet tray. Detective Vance checked the flashlight batteries and immediately knew the killer was a close family member. How?
The batteries were brand new
A flashlight left running in a closed vault would have drained its batteries if it had been left on since the robbery hours ago. Fresh batteries meant someone turned it on recently, implying they had access to the vault's spare supplies.
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: Hard. More like this: Detective riddles with answers or try Truth & Lie Island for a different kind of puzzle.
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