Inspector Vance found the victim slumped over a desk with a frozen carbon dioxide sculpture melting nearby, a warm space heater glowing, and a half-eaten sandwich. The note left behind read: 'I melted my own evidence.' Vance immediately arrested the victim's assistant for murder. Why?
The assistant
Solid carbon dioxide (dry ice) sublimes into gas directly; it does not melt into a liquid. The presence of a puddle from 'melting' dry ice proves someone staged the scene with regular water ice, exposing the fake suicide.
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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