Case 062
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 Sam or Morgan is guilty.”
Lane
“Cameron is guilty.”
Reese
“Lane is innocent.”
Sam
“Lane and Morgan are both innocent.”
Morgan
“Lane and Sam are both innocent.”
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.