In this paper, I revisit the first case of direct French intervention into Tunisian policy in the years preceding the establishment of the protectorate: the passage of the ʿahd al-amān (Security Pact). This law is intimately tied to the Bathou Sfez affair, in which a Jew by that name was executed after being convicted of blasphemy in June 1857. Previous scholars have generally stayed close to the interpretation of events advanced by minister and chronicler Ibn Abī al-Ḍiyāf, who asserts that the Muḥammad Bey influenced the composition of the court and pressured it to pass a capital sentence for his own political ends. Based on recently uncovered archival material, I argue that these claims are not supported by contemporary documentation. Rather, the documentation surrounding the trial shows a court that strictly adhered to both procedural and jurisprudential norms. No independent evidence indicates either that the bey intervened as alleged, nor even that such an intervention would have affected the outcome had it happened. This cause célèbre, despite being used as pretext for fundamental legal reform, represents a functional legal system that respected the norms of the sharīʿa. If there existed a need for reform, it was not because the system was broken, but because the system satisfied autochthonous needs rather than those of the Second French Empire. Ibn Abī al-Ḍiyāf’s depiction, I argue, does not represent a disinterested account of the events but rather a retrospective and self-justifying narrative of his own role in the crafting of the new legislation that served European imperial and commercial interests no less than it defended the rights of Tunisian subjects. Ibn Abī al-Ḍiyāf remains a major source for the historiography of this period; I call for a deeper skepticism of his chronicle in interpreting the history of nineteenth-century Tunisia.