Answer:
Dogberry.
Step-by-step explanation:
Dogberry is the character first discover the proof of the truth about Hero's innocence. Dogberry who is a Constable that is a master of malapropisms discovers the evil trickery of the Don John. In the end of the story, Don John is captured. Claudio was tricked by the villain Don John into thinking that Hero was cheating on him with another man that make the heart of Claudio against the Hero.