Case 145
The Disabled Camera
A security camera was deliberately switched off.
Rule: exactly one suspect is guilty. The guilty suspect lies. Every innocent suspect tells the truth.
Harper
“Quinn is innocent.”
Frankie
“Harper is innocent.”
Sam
“Either Harper or Morgan is guilty.”
Morgan
“Harper is guilty.”
Quinn
“Neither Harper nor Sam is guilty.”
Who is guilty?
Solution: Morgan
If Morgan is guilty, Morgan's statement is false and every other statement is true. Testing the other suspects creates at least one contradiction.