CASE ZERO
Case 241

Who is guilty?

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

Maya: “None of Maya, Noah or Iris is guilty.”
Noah: “Neither Maya nor Lena is guilty.”
Lena: “The guilty person is either Lena or Owen.”
Owen: “The guilty person is one of Maya, Noah or Iris.”
Iris: “The guilty person is either Noah or Owen.”
Random case
Solution: Owen 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.