- Cornwallis introduced some significant reforms in the sphere of judicial administration and tried to complete the unfinished work of Warren Hastings. During his period number of revenue districts was reduced from 35 to 23 in the Presidency of Bengal. The collector was the head of the district. In 1787 district courts were presided over by the collector. The collectors were vested with magisterial powers and empowered to administer criminal justice.
- In 1790-92 further changes were made in the administration of criminal justice. The Faujdari Adalats of the districts were abolished and in their place four circuit courts were established at Dacca, Patna, Calcutta and Murshidabad. These courts were presided over by two covenanted servants of the company who decided the cases with the help of Qazis and Muftis. The Sadar Nizamat Adalat was again shifted from Murshidabad to Calcutta. The Muhammadan Judge of this Adalat was removed and in his place the Governor General and Council presided over the Sadar Nizamat Adalat.
- By 1793 the judicial reforms of Cornwallis took the final shape and were embodied in the famous Cornwallis Code. Separation of powers was the basis of the new reforms. The collector was deprived of all his judicial and magisterial powers. The judges tried all civil cases in the districts.
- The collector was required to look after the administration and to realise the revenue of the district. Under the subordination of the District Judge Civil and criminal courts of Lower grade were established in which the Munsif and Sadar Amin tried the minor cases of the people. Appeals could be made to district court against the decisions of the Lower Courts.