Case 003
The Stolen Watch
A valuable watch disappeared during a private gathering.
Rule: exactly one suspect is guilty. The guilty suspect lies. Every innocent suspect tells the truth.
Noah
“Casey is innocent.”
Parker
“Quinn and Casey are both innocent.”
Quinn
“Taylor is guilty.”
Taylor
“Either Noah or Parker is guilty.”
Casey
“Quinn is innocent.”
Who is guilty?
Solution: Taylor
If Taylor is guilty, Taylor's statement is false and every other statement is true. Testing the other suspects creates at least one contradiction.