Case 277
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
“Either Blake or Riley is guilty.”
Blake
“Neither Kai nor Rowan is guilty.”
Riley
“Either Blake or Kai is guilty.”
Kai
“Sam and Rowan are both innocent.”
Rowan
“Sam and Blake are both innocent.”
Who is guilty?
Solution: Riley
If Riley is guilty, Riley's statement is false and every other statement is true. Testing the other suspects creates at least one contradiction.