Clues & Culprits › Clue types › If–then clues
If–then clues
Conditionals like "If Gus is a criminal, then so is Hana". One-way only, but the contrapositive always holds.
If Gus is a criminal, then so is Hana.
An if–then clue promises something only when its condition is met. "If Gus is a criminal, then so is Hana" says nothing at all when Gus is innocent — Hana could be either.
The two moves that always work
- Forward: prove the condition (Gus is a criminal) and you have proven the result (Hana is a criminal).
- Backward (the contrapositive): prove the result is false (Hana is innocent) and the condition must be false too (Gus is innocent).
The two moves that never work
- Gus is innocent → tells you nothing about Hana.
- Hana is a criminal → tells you nothing about Gus.
"If" never means "if and only if". When a case needs both directions, it will say so with a same-verdict clue instead.
How it combines with other clues
Use a count to test the condition. If assuming "Gus is a criminal" would force Hana to be a criminal too, and a row count can't fit two more criminals, then Gus must be innocent. That is a typical two-clue step.
Real examples from recent cases
If Juno is a criminal, then I'm innocent.— Leo, intern (D3) in Oct 25, 2026 Hard: An Allergy to Tuesdays
If Willa is a criminal, then Idris is innocent.— Queenie, baker (B4) in Oct 25, 2026 Evil: Duck 1,417 Wins by Thirty Yards
If I'm a criminal, then Bruno is innocent.— Freya, keeper's assistant (B2) in Oct 24, 2026 Medium: Breakfast with the Gorillas
If Iris is innocent, then so is Gus.— Rufus, keeper's assistant (B5) in Oct 24, 2026 Medium: Breakfast with the Gorillas
Questions
What does “If Gus is a criminal, then so is Hana.” prove?
Conditionals like "If Gus is a criminal, then so is Hana". One-way only, but the contrapositive always holds.
Where do if–then clues appear most?
In every difficulty. In Easy cases they usually settle someone on their own; in Hard cases they tend to combine with other clues.
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