An art dealer was found dead in his gallery, poisoned by a rare toxin smeared on the handle of his office door. The door opened inward. The coroner noted the dealer's left hand was severely contaminated, while his right hand was completely clean. Detective Lane deduced the killer must have been left-handed. How?
The door handle mechanics
If the door opened inward and the handle was on a certain side, a right-handed person would naturally grasp the handle with their right hand. However, if the victim used his left hand to open an inward-opening door from a specific angle, or if the toxin was placed on the inside latch, a left-handed person approaching from the hallway would instinctively reach across with their left hand. Wait, if the door opens inward and the handle is on the right side of the door frame, a person uses their right hand. If the victim's left hand was contaminated, he opened it with his left hand, which is awkward unless he was holding something in his right hand.
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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