Case 152
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.
Frankie
“Dakota is guilty.”
Kai
“Frankie and Parker are both innocent.”
Dakota
“Either Kai or Parker is guilty.”
Peyton
“Either Dakota or Parker is guilty.”
Parker
“Frankie is innocent.”
Who is guilty?
Solution: Dakota
If Dakota is guilty, Dakota's statement is false and every other statement is true. Testing the other suspects creates at least one contradiction.