Case 065
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
“Hayden is guilty.”
Riley
“Hayden is innocent.”
Rowan
“Riley is innocent.”
Hayden
“Blake is guilty.”
Marley
“Either Blake or Rowan is guilty.”
Who is guilty?
Solution: Blake
If Blake is guilty, Blake's statement is false and every other statement is true. Testing the other suspects creates at least one contradiction.