No matter how high, no one is out of reach

The highest ranking officials investigated for corruption before Zhou Yongkang were deputy-national level officials, such as the vice-chairmen of the Standing Committee of the National People's Congress, the National Committee of the Chinese People's Political Consultative Conference, and the Central Military Commission. Zhou, who was a former member of the Standing Committee of the Political Bureau, is up till now the highest ranking official ever to be investigated for corruption.

China's new national leadership headed by President Xi Jinping has demonstrated zero tolerance toward corruption and absolute resolve to carry through the crackdown since the 18th Communist Party of China National Congress. The investigation of Zhou has shown their unbiased attitude toward all the officials irrespective of their rankings.

The disregarding of the titles of the "tigers", or corrupt officials holding important positions, is a test of how tough the top leaders will be against the rotten apples.

The central leadership is expected to carry out bold measures through deeper reforms to eradicate corruption.

Ren Jianming is director of the Clean Governance Research and Education Center at Beihang University.