CASE ZERO
Case 203

Who is guilty?

Exactly one suspect is guilty. The guilty suspect lies. Every innocent suspect tells the truth.

Ruby: “The guilty person is one of Ruby, Theo or Finn.”
Theo: “The guilty person is either Finn or Jade.”
Mila: “The guilty person is either Theo or Finn.”
Finn: “The guilty person is one of Ruby, Theo or Jade.”
Jade: “None of Theo, Mila or Jade is guilty.”
Random case
Solution: Finn is guilty. Testing each possible culprit leaves this as the only assignment where the culprit's statement is false and all four innocent statements are true.