Case 130
The Stolen Prototype
A prototype vanished from a secured workroom.
Rule: exactly one suspect is guilty. The guilty suspect lies. Every innocent suspect tells the truth.
Elliot
“Either Logan or Alex is guilty.”
Casey
“Alex is innocent.”
Logan
“Casey and Alex are both innocent.”
Alex
“Either Elliot or Rowan is guilty.”
Rowan
“Logan and Alex are both innocent.”
Who is guilty?
Solution: Elliot
If Elliot is guilty, Elliot's statement is false and every other statement is true. Testing the other suspects creates at least one contradiction.