Case 046
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.
Blake
“Drew and Lane are both innocent.”
Drew
“Neither Blake nor Quinn is guilty.”
Dakota
“Either Blake or Quinn is guilty.”
Quinn
“Neither Drew nor Lane is guilty.”
Lane
“Blake is innocent.”
Who is guilty?
Solution: Dakota
If Dakota is guilty, Dakota's statement is false and every other statement is true. Testing the other suspects creates at least one contradiction.