judge and other court of complaint (mazalim) officials, who were investigated and imprisoned as a result. Their cases were presided over by Ishaq ibn Ibrahim al-Mus'abi, and they were publicly displayed and treated in a harsh manner. Downfall and death Following the death of al-Wathiq in 847, Ibn Abi Du'ad formed a council with Ibn al-Zayyat and other senior officials to determine who should succeed the caliph, eventually settling on al-Wathiq's brother Ja'far. Ibn Abi Du'ad gave the nominee the regnal title of al-Mutawakkil, and the latter was accordingly invested with the caliphate. Al-Mutawakkil's reign (r. 847–861) marked a significant break with the policies of al-Mu'tasim and al-Wathiq. The new caliph was determined to eliminate the officials who had played a dominant role in the governments of his two predecessors, and in the first years of his rule he succeeded in killing or removing from power the majority of these men, including Ibn al-Zayyat and the chamberlain Itakh. Al-Mutawakkil also decided to diverge away from the religious policies of the previous caliphs, opting instead to put a stop to the controversy over whether the Qur'an was created or uncreated. Although he was not a partisan of the traditionalist party, he gradually abandoned Mu'tazilism and suspended the , ultimately putting an end to the doctrinal regime that had been in place since 833. The new caliph initially took no action against Ibn Abi Du'ad, who continued to appoint qadis to provincial cities. Less than a year after al-Mutawakkil's accession, however, the chief judge suffered a debilitating stroke that left him partially paralyzed, and his son Muhammad was forced to take up the actual discharge of his duties. Muhammad proved to be less influential than his father, and the family's standing declined as al-Mutawakkil spent the next several years taking hostile steps against the Mu'tazilites, dismissing a number of Ibn Abi Du'ad's qadis from office and ordering an end to debate over the nature of the Qur'an. In late 851, al-Mutawakkil decided to completely remove Ibn Abi Du'ad from power and stripped Muhammad of his positions in the mazalim courts. He also ordered that the estates of Ibn Abi Du'ad and his family to be seized and liquidated, and Muhammad and his brothers were placed into prison. At the same time, the caliph took steps to definitively end the . In place of Ibn Abi Du'ad, Yahya ibn Aktham was re-appointed as