Harakat al-Shabaab al-Mujahideen, usually referred to as al-Shabaab (the youth), is known primarily as a Somali terrorist group. But since the end of 2008, it has functioned as a state power in large parts of Southern and Central Somalia. In this article, I analyze the main legal body of the group: the qāḍī court. In order to establish law and order in their territories, al-Shabaab has applied their own version of sharī'a. The article reveals that al-Shabaab's application of criminal law follows the inherent logic of classical Islamic legal doctrines on several points. However, the al-Shabaab courts tend to overlook many of the strict requirements regarding evidence and procedure that were outlined by the medieval Muslim scholars in order to humanize Islamic law. Therefore, the legal reality of al-Shabaab's regime is far more brutal than that of most other Islamic-inspired regimes in the contemporary Muslim world. Al-Shabaab's practice of Islamic criminal law may be seen not only as a means to exercise control through fear but also as an effective way of filling the vacuum of insecurity and instability that has followed twenty years of violence and the absence of state institutions in its territories. I argue that, in order to understand al-Shabaab's current practice of criminal law, one has to take into consideration the group's jihadi-Salafi affiliation. According to Salafi notions, sharī'a is not only a means to an end, but an end in itself. As such, sharī'a (i.e., God's divine law) is the visual symbol of an Islamic state. Consequently, the application of Islamic criminal law, and especially of the ḥudūd punishments, provides al-Shabaab with political-religious legitimacy.