Christian C. Sahner (University of Oxford) has published the following article: "Zoroastrian law and the spread of Islam in Iranian society (ninth-tenth century)," Bulletin of the School of Oriental & African Studies (2021). Here's the abstract:
This article explores three important Zoroastrian legal texts from the ʿAbbasid period, consisting of questions and answers to high-ranking priests. The texts contain a wellspring of information about the social history of Zoroastrianism under Islamic rule, especially the formative encounter between Zoroastrians and Muslims. These include matters such as conversion, apostasy, sexual relations with outsiders, inheritance, commerce, and the economic status of priests. The article argues that the elite clergy responsible for writing these texts used law to refashion the Zoroastrian community from the rulers of Iran, as they had been in Late Antiquity, into one of a variety of dhimmī groups living under Islamic rule. It also argues that, far from being brittle or inflexible, the priests responded to the challenges of the day with creativity and pragmatism. On both counts, there are strong parallels between the experiences of Zoroastrians and those of Christians and Jews, who also turned to law as an instrument for rethinking their place in the new Islamic cosmos. Finally, the article makes a methodological point, namely to show the importance of integrating Pahlavi sources into wider histories of Iran and the Middle East during the early Islamic period.
Further information is available here.