The execution of the former vice-mayors of Hangzhou and Suzhou on Tuesday for taking huge sums of money in bribes, demonstrates the authorities' resolution to fight against corruption.

But the way both officials extracted bribes from real estate developers points to institutional loopholes and a lack of effective supervision, which made it possible for them to abuse their power.

Xu Maiyong, former vice-mayor of Hangzhou, capital city of East China's Zhejiang province, got land for realtors in exchange for kickbacks. He received 145 million yuan ($22.4 million) in bribes and embezzled more than 53 million yuan. He even got a piece of land that originally belonged to a university for a realtor and then helped the realtor get the land purchase payment of 71 million yuan that should have gone to the university. He became popularly known as the vice-mayor in possession of a lot of money, a lot of houses and a lot of women.

Jiang Renjie, the former vice-mayor of Suzhou in neighboring Jiangsu province, received his bribes through a company registered by a realtor that was actually under his son's control. His son borrowed money from the real estate developer who got the right to develop a piece of land in exchange. The realtor said later that Jiang got an 80-million-yuan kickback in this way.

It seems both of them were able to bend the rules in favor of a particular realtor when it came to the purchase of land use rights for real estate projects.

Both officials were only vice-mayors, yet they could still use their power to get land for real estate developers. What if they had been more powerful?

Obviously, both officials had ways to circumvent the institutional barriers to the abuse of power, or there are serious loopholes in the institutions that facilitated their corruption.

The Supreme People's Court published the two cases in order to let other officials learn from the two mayors' transgressions. But that is not enough.

Clearly, officials need to know that the law will show no leniency once they abuse their power. But it is unrealistic to expect officials to remain honest simply because they are afraid of being caught.

What is urgently needed is a mechanism that makes it difficult for officials to abuse the power in their hands.

It is not too late to mend the fences.

Collective leadership needs to be exercised by the mayor and the vice-mayors in a city government, and as both cases once again justify the widespread belief that real estate development is a hotbed of corruption, an open tender competition must be held for the sale of land for real estate development.