This article examines the lives of two Portuguese conversos, Gaspar Robles and Francisco Home, a nephew and his uncle, both tried by the Inquisition tribunal in seventeenth-century colonial Mexico during the decade leading up to the Gran auto de fé of 1649. However, their trajectories were vastly different. Gaspar Robles voluntarily approached the Inquisition tribunal confessing his own and his family's secret Jewish practices. He incriminated his father, his three uncles, and many other acquaintances who formed part of the converso community in New Spain precipitating the mass prosecutions of many in the converso community. In contrast, his uncle Francisco Home was also arrested soon after Gaspar's confession. He was tried and tortured, and he eventually confessed to his own crypto-Judaism. However, he protected some in the converso community in sharp contrast with his nephew's voluntary confession. Through close examination, this article explores the role of individual and community identity among conversos in New Spain to explain why the nephew confessed to the tribunal sealing the fate of his immediate family and that of a whole community. It argues that in cases such as that of Gaspar Robles familial ties proved more a liability than a protection and the final outcome was contingent on a combination of religious and ethnic identity, the process of migration, and individual circumstances.In 1641, thirty-two year old member of a Portuguese merchant family Gaspar Robles voluntarily appeared before the Holy Office of the Inquisition in Mexico City denouncing himself and his kinsmen as crypto-Jews (individuals who professed to be Christian in public, but practiced Judaism in secret). 1 Rare was the crypto-Jew who made a voluntary selfdenunciation before the Inquisition tribunal. More often, the Holy Office of the Inquisition would build a case based on information gathered from voluntary denunciations, or sometimes from testimonies provided by individuals already in the hands of the tribunal whom they questioned, at other times under the duress of torture or the threat of it. Since the religious purpose of the Inquisition was to protect the Christian community from heresy and deviant practices, the tribunal had in Gaspar Robles the perfect instrument to fulfill its duties.