Fox Hunt: Melbourne grandmother Zhou Shiqin in Beijing's sightsFox Hunt: Australia closer to extradition treaty on wanted Chinese 'fugitives'Chinese president's war on corruption finds its way to BrightonChinese police pursued a man to Australia on a 'fox hunt' without permission
Beijing: A Melbourne grandmother wanted by Beijing for corruption has quietly returned to the Chinese mainland to cooperate with police despite protesting her innocence. 
The case underlines the pervasive pressure tactics employed by Chinese authorities outside the bounds of bilateral law enforcement cooperation in its zealous pursuit of what it says are corrupt officials and international fugitives who have absconded overseas, including Australia.
Along with other cases involving Australian residents, it also prompts questions over the bona fides of China's much-vaunted Fox Hunt and Sky Net operations, which was relaunched for the year last week.
Accused of embezzling millions of yuan from a state-owned railway authority more than a decade ago, the decision by Zhou Shiqin, 64, to place herself voluntarily at the mercy of China's opaque judicial system stems from the pressure she has been under since authorities published her Interpol red notice prominently on state media outlets a year ago, announcing her on a list of the Communist Party's top 100 wanted criminals worldwide.
"We did think at first it would be dangerous for her to return," Ms Zhou's lawyer Ma Hean told Fairfax Media on Monday. "But she can't let it go. The psychological pressure on her is extraordinary."
While Australia is moving to ratify a long-dormant extradition treaty with China, it is understood there has been no pressure from Australian law enforcement agencies for Ms Zhou to cooperate with Chinese police.
Despite repeated offers to provide a cache of documents which Ms Zhou says exonerates her of any wrongdoing, Chinese authorities have insisted she return in person before moving her case forward. Ms Zhou arrived by plane in the north-eastern city of Dalian on Thursday.
"Although they can't really say so [publicly], [Chinese investigators] do think there is a problem with this case," Mr Ma said.
In part, Ms Zhou's return is a calculated gamble that old political squabbles and manipulation of the party-run judiciary has subsided sufficiently under Mr Xi's push for rule of law for her evidence will be heard fairly. But local prosecutors will be loathe to admit to any errors in the initial investigation, and any not-guilty verdict will open up questions as to where the misappropriated funds had really gone.
And in other cases involving Australian residents reviewed by Fairfax Media, the propaganda qualities of the anti-corruption drive have often been the priority.
When Brisbane man and Fox Hunt target Huang Houzhen agreed to return to his native Heilongjiang in   November 2014 to dispute embezzlement charges, he was shocked to find a photo of him being met by police at the airport plastered prominently on state media websites and local newspapers the next day. Authorities pixellated the area around Mr Huang's hands, as if to give the impression that he had been handcuffed.
Local authorities basked in the credit for successfully tracking down an international 'fugitive'. Instead, Mr Huang contends nearly 200 million yuan ($40 million) of cash and assets in his private heating company had been stolen by government officials before he was framed for embezzlement in 2008. He left for Australia the next year.
Mr Huang told Fairfax Media he returned voluntarily after being verbally assured a fair investigation, and contrary to the suggestion of local reports, he was free to move around in mainland China.
His case was delayed for more than a year as local authorities sought a face-saving compromise. Earlier this month, a local court quietly handed down a decision, finding him guilty yet deciding not to impose a custodial sentence.
Mr Huang will now negotiate with the local city government in an effort to retrieve his investors' funds.
China's anti-corruption agency has trumpeted the return of more than 1000 overseas suspects from 68 countries worldwide as proof of the major success of its so-called Fox Hunt and Sky Net operations, part of President Xi Jinping's broader anti-corruption drive. The officially-released figure includes 26 suspects from its most-wanted list of 100.
Those publicly named as likely residing in Australia mainly include low-level officials, suggesting China wants to establish precedents in bilateral law enforcement cooperation before requesting some of the bigger and more politically sensitive targets in its sights.
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