But, as a retired customs officer explained, this was made worse by the organisational structure of the police force, in the form of the staff sergeant and sergeant major. 'A staff sergeant, while being lowly on the organisational chart, actually exercised enormous power,' he said in an interview with the Post yesterday on condition that he not be named.

'You didn't have a choice. If you refused to take bribes, you were thumbing your nose at your superiors, you would be upsetting careful arrangements maintained between crime and law enforcement - upsetting the balance, so to speak.'

There were three or four staff sergeants at any one time, and they were in charge of all the rank-and-file officers in their areas. Unlike today's division by districts, they were responsible for huge geographic areas - Hong Kong Island, Kowloon - Yau Ma Tei had its own sergeant - and New Territories. A sergeant major lorded over them.

Notionally, the staff sergeant ranked below an inspector, but even senior inspectors had to show them respect. This is because these powerful sergeants knew the pulse of the street, and effectively controlled gang activities and the territories each was allowed to operate - all the while taking a large chunk of commissions. Peter Godber, one of the ICAC's most high-profile cases, was a chief superintendent.

The sergeants' immediate boss, the sergeant major, communicated directly with the assistant commissioners.

'Police staff sergeants could directly communicate with a superintendent or senior superintendent who would probably be on the take,' the former customs officer said. 'They were powerful because they were the links between the top brass and the low ranks.'

The four sergeants - Hon, Lui Lok, Nan Kong and Ngan Hung - effectively divided Hong Kong among themselves.

Hon entered the police in September 1940 and retired in August 1971. When he retired, he had a fortune estimated to be worth more than $4 million on total salaries of $193,852 over 31 years in the force.

In 1976, the ICAC bought charges against Hon for alleged bribery and applied for an arrest warrant but he had moved to Canada. The government sought to have him extradited in May 1977 but the bid failed when he fled to Taiwan, where he died in August 1999.

Lui Lok

The court gave a judgment in favour of the ICAC in 1986.

The amount of the settlement was not disclosed. Lui sought refuge in Taiwan in 1974

Tsang Kai-wing

The ICAC recovered $4.35 million by auctioning his La Salle Road home in 2005 after 10 years of

civil proceedings

SCMP

Graphic

Ma Man-leung

The ICAC recovered $130 million worth of assets through civil proceedings in 2000. Ma was released on bail and fled to Taiwan in May 1977 while his case was still under investigation. He died there in 1990

Cheung Wing-shu

The court gave a judgment in favour of the ICAC in 2003 The amount of the settlement was not disclosed

Peter Godber

$400,000 worth of assets were confiscated in the 1980s. Bids to recover another $6.4 million from him are continuing. He is reportedly living in Spain after serving a four-year jail term in 1975