The response he sees convinces wilson of what

The applause from the court convinces Wilson that he is not only right in his convictions but an expert in forensics. Wilson makes two revelations that shock the townspeople and bring about Tom's demise: he man the town has come to know as Tom Driscoll is in fact the slave Valet de Chambre, switched in infancy by his mother, and this false heir is guilty of murdering Judge Driscoll. Roxy throws herself to her knees and begs for mercy, while the usurper is taken in custody.