In the meantime, Pierre Guerre had asked around and believed to have found the true identity of the impostor: Arnaud du Tilh, a man with a poor reputation from the nearby village Sajas (not the Gascon commune of Tilh, 150 km west of Sajas in Dax).
The impostor was convicted and sentenced to death for adultery and fraud; the public sentencing on September 12, 1560, during which the accused maintained his innocence, was attended by the young Montaigne.
Afterwards, Arnaud du Tilh confessed: he had learned about Guerre's life after two men confused him with Guerre, and he had then decided to take Guerre's place, with two conspirators helping him with the details.
Proceeding with the confrontations, the said du Tilh requested that the said Rols be sheltered and at liberty, to avoid the threat of being compelled to bear false testimony; the which was ordered and done.
This matter being brought to court, the said du Tilh, prisoner, was sentenced and condemned to lose his head, and to be quartered, and the decision announced to the saId de Rols.
Afterwards to carry out the said verdict, this du Tilh was brought from the Conciergerie to Artigat, where the execution was to take place, and there was heard by the said judge of Rieux, before whom, the sixteenth of September of the said year 1560, he confessed at great length his impudent and daring misdeed.