Case 010
The Missing Ledger
A confidential ledger disappeared from the office.
Rule: exactly one suspect is guilty. The guilty suspect lies. Every innocent suspect tells the truth.
Peyton
“Finley and Taylor are both innocent.”
Finley
“Neither Peyton nor Harper is guilty.”
Lane
“Either Peyton or Finley is guilty.”
Taylor
“Lane is guilty.”
Harper
“Either Finley or Lane is guilty.”
Who is guilty?
Solution: Lane
If Lane is guilty, Lane's statement is false and every other statement is true. Testing the other suspects creates at least one contradiction.