A security consultant was hired to test a bank vault's security system. He locked himself inside the vault at 9:00 PM, intending to trigger the silent alarm from within. At 9:30 PM, the guards opened the vault using their digital overrides and found the consultant bound and gagged inside, with his briefcase missing. The guards insisted they never opened the door early. The consultant claimed he never touched the alarm because he was ambushed the second the door clicked shut. Detective Ross arrested the guards. What gave them away?
The vault door timer and logs recorded that the digital override was entered at 9:15 PM.
Digital vault locks keep an electronic audit log of every time the code is entered. The log proved the guards opened the door during the simulation, contradicting their claim that they never opened it early.
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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