Case 111
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 Logan nor Casey is guilty.”
Finley
“Either Drew or Casey is guilty.”
Drew
“Logan is guilty.”
Logan
“Neither Finley nor Casey is guilty.”
Casey
“Finley is innocent.”
Who is guilty?
Solution: Drew
If Drew is guilty, Drew's statement is false and every other statement is true. Testing the other suspects creates at least one contradiction.