Mr Clean catches China's graft tigers by the tail

Behind China's aggressive drive to root out corruption is Wang Qishan, a historian-turned-economist who once felt so bad about getting free parking that he reportedly sent a colleague back to pay the fee.

President Xi Jinping launched the anti-corruption campaign after becoming Communist Party chief in November.

So far the party has announced the investigation or arrest of eight senior officials, including three from the 376-member elite Central Committee. Among them, former executives from oil giant PetroChina are being investigated in what appears to be the biggest graft probe into a state-run firm in years.

Wang, 65, heads the Central Commission for Discipline Inspection and ranks sixth in the party hierarchy. His power far exceeds this, said Cheng Li, a fellow at the Brookings Institution in Washington and an expert on Chinese politics.

"I would say that Wang Qishan is the second most powerful person next only to Xi Jinping," he said.

Given the secretive nature of China's Communist Party, there are few details on what Wang has done as its top graft-buster, a role he assumed when Xi became party chief.

Wang keeps a low profile and his public appearances and comments, like those of all top Chinese leaders, are usually scripted. He rarely gives interviews.

But observers said the fingerprints of the urbane former banker were visible in the anti-corruption campaign and in related efforts to force officials to behave less extravagantly.

"He is the lead actor in this," said Zhang Ming, a professor at Renmin University in Beijing.

Immunity for elite removed

For example, it was Wang who proposed the party scrap a decades-old unwritten rule that exempted incumbent and retired members of the seven-man Politburo Standing Committee, of which he belongs, from investigation for corruption, a source with direct knowledge of the matter said.

That landmark move was approved earlier this year by the Standing Committee, China's top political decision-making body, sources who have ties to the leadership or direct knowledge of the matter have told Reuters.

Wang has also reorganised parts of the discipline inspection commission and added two offices so the body can deepen its investigations into provincial leaders.

And one of the earliest initiatives Xi unveiled was a set of guidelines for officials that aimed to cut bureaucracy and formality.

"This came from the discipline commission," said Li of the Brookings Institution.

"He and Xi Jinping have a very, very good partnership."

To be sure, China has announced corruption crackdowns before that have met with little success. Experts say only deep and difficult political reforms will move the needle.

"If the anti-graft campaign is sustained and expanded, it could begin to challenge the party's systemic problems with corruption, but it's far too early to say that the government is committed to that," said Duncan Innes-Ker, senior China analyst at the Economist Intelligence Unit.

Like his predecessors, Xi says corruption threatens the party's very survival. He has said he wants to show he is serious by going after "tigers", or political heavyweights, not just "flies".

Some questioned the wisdom of moving Wang away from his role as a leading economic policymaker. A protege of former premier and economic reformer Zhu Rongji, he was even viewed as a dark-horse candidate for premier before the new leadership lineup was announced in November.

Now that the Chinese economy is showing signs of stability, the decision to deploy a man widely known as "the chief firefighter" to the corruption front might be a good call.