Case 238
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.
Reese
“Neither Blake nor Frankie is guilty.”
Parker
“Either Reese or Blake is guilty.”
Drew
“Reese and Frankie are both innocent.”
Blake
“Neither Drew nor Frankie is guilty.”
Frankie
“Parker is guilty.”
Who is guilty?
Solution: Parker
If Parker is guilty, Parker's statement is false and every other statement is true. Testing the other suspects creates at least one contradiction.