The trial last week of Wen Qiang, allegedly one of the key figures in the biggest crackdowns on gang crimes in the country, does not just serve as a warning to government officials against the abuse of power but also shows how complicated the fight against corruption can be.

Rome was not built in a day. Evidence has shown that Wen, as former director of the Chongqing municipal bureau of justice, did not collect his huge fortune illegally in a matter of days.

The long list of the money he has taken on different occasions and in different quantities during the years when he was in power unveils what a person he is and how unscrupulous he has been in accepting money and properties his subordinates have given him.

The uncovering of a huge sum of money hidden underneath a water pool by Wen's wife as well as his failure to tell where his property worth millions of yuan came from have added to the mystery and drama of what is yet to be exposed about this man who was once a heroic policeman.

Unlike some of his counterparts, who have tried to defend themselves by explaining that they didn't know that accepting money from subordinates is a crime, Wen argues that the money he received should not be regarded as bribes since he did not promote or did any favors for those who gave him money. He even defended that the properties or money he received on his birthday should not be referred to as bribes.

When he found it impossible to deny the crimes against clear evidence, he immediately expressed his willingness to be punished according to the law.

We will never know if all the bribes this corrupt official has allegedly collected by abuse of power have been uncovered. The impression from the trial is that Wen has been trying to defend himself in whatever manner possible.

As all know, the severity of a sentence for a corrupt official depends directly on the value of bribes he or she has taken. That explains why Wen has tried to deny some of the money he has received as bribes and refuses to identify the sources of quite a large sum of money in his possession.

Although the defense at court showcases progress in China's trial system, this is exactly where the fight against corruption is becoming increasingly complicated. The way the officials hide their money, destroy evidence and blur the line between gifts and bribes have made it hard for prosecutors to collect evidence against them.

And there is usually a network around corrupt officials, making the fight against corruption much more difficult and complicated.

Yet, this trial should provide enough fodder for the building of a mechanism to stem corruption as soon as it takes place or reduce its occurrence to the minimum. And however challenging, the line between accepting gifts and taking bribes should be clarified.