Case 077
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.
Logan
“Neither Noah nor Riley is guilty.”
Noah
“Logan and Riley are both innocent.”
Riley
“Neither Logan nor Marley is guilty.”
Marley
“Either Logan or Emery is guilty.”
Emery
“Either Logan or Riley is guilty.”
Who is guilty?
Solution: Emery
If Emery is guilty, Emery's statement is false and every other statement is true. Testing the other suspects creates at least one contradiction.