Judicial performance is a complex subject of great social importance; however, it is little studied under the lens of Public Administration. The work performed by the judges is the central element of judicial performance; therefore, identifying variables that influence the performance of these professionals can increase the knowledge in this area. Thus, this study aims to explain what influences the productivity of state judges of the first instance court in Brazil. Data regarding the performance of 581 judges holding the first instance of the State Court of Minas Gerais were analyzed using statistical techniques. The results indicate that the number of support staff and the workload are positively correlated with the productivity of judges. Explanations are presented for the results found and discussed theoretical and practical implications for the administration of courts in the country.