Case 106
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.
Drew
“Sam and Cameron are both innocent.”
Harper
“Either Drew or Cameron is guilty.”
Sam
“Either Harper or Cameron is guilty.”
Peyton
“Drew is innocent.”
Cameron
“Peyton is innocent.”
Who is guilty?
Solution: Harper
If Harper is guilty, Harper's statement is false and every other statement is true. Testing the other suspects creates at least one contradiction.