Case 338
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.
Cameron
“Either Elliot or Kai is guilty.”
Elliot
“Either Cameron or Kai is guilty.”
Hayden
“Kai is innocent.”
Marley
“Either Cameron or Elliot is guilty.”
Kai
“Either Cameron or Marley is guilty.”
Who is guilty?
Solution: Cameron
If Cameron is guilty, Cameron's statement is false and every other statement is true. Testing the other suspects creates at least one contradiction.