The Communist Party yesterday said its fourth plenum will be held from October 20-23 and would focus on improving the administration of law. Emphasising the rule of law was crucial for building a prosperous society and enhancing the ability of the party to govern, said a Politburo statement issued after its meeting yesterday. Reforms to strengthen the rule of law are expected to be discussed and adopted during the four-day closed-door meeting, state television reported. Measures will be taken to improve the legal system and the mechanism for overseeing it. The South China Morning Post reported in May the party leadership wanted the fourth plenum of the Central Committee to focus on the rule of law amid the corruption probe into former national security tsar Zhou Yongkang . Sources said that President Xi Jinping might use the meeting to pledge to safeguard the constitution and fight graft, even at the highest levels of the government. The Politburo statement said rule of law should be promoted under the leadership of the party. The authority of the constitution and the rights of the people should be protected, while justice and national security should be safeguarded, it added. Mao Shoulong , a professor of public administration at Renmin University in Beijing, said he expected measures to be taken to clearly define the powers of the judiciary and various other agencies. The Supreme People's Court announced in July a five-year plan to boost judicial independence from the government, giving judges more authority. Hu Xingdou , a political analyst at the Beijing Institute of Technology, said the plenum would be a milestone for the president after setting the direction for economic reforms during the third plenum last year. "The meeting will be very important for Xi's legacy because economic reform and judicial reform will be the two cornerstones of his administration," he said.