Case 224
The Lost Access Card
A master access card was taken from the reception desk.
Rule: exactly one suspect is guilty. The guilty suspect lies. Every innocent suspect tells the truth.
Sam
“Neither Kendall nor Peyton is guilty.”
Kendall
“Either Reese or Emery is guilty.”
Reese
“Peyton is guilty.”
Emery
“Kendall and Peyton are both innocent.”
Peyton
“Neither Sam nor Kendall is guilty.”
Who is guilty?
Solution: Reese
If Reese is guilty, Reese's statement is false and every other statement is true. Testing the other suspects creates at least one contradiction.