CASE ZERO
Case 107

Who is guilty?

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

Ruby: “None of Ruby, Mila or Finn is guilty.”
Theo: “Neither Finn nor Jade is guilty.”
Mila: “Theo is innocent.”
Finn: “The guilty person is one of Ruby, Mila or Finn.”
Jade: “The guilty person is either Ruby or Mila.”
Random case
Solution: Ruby 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.