Detective Vance was handed a suicide note written in pencil. The grieving widow claimed her husband wrote it right before he died. Vance rubbed a cotton swab over the paper and immediately knew the widow forged it. What did the swab test reveal?
The graphite smudge test revealed multiple layers of erased text underneath, showing it was traced or written over a different template.
Erasure marks under pencil writing indicate drafting or forgery rather than a spontaneous single-sitting note.
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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