A Chinese national named Bao Fengshan was sentenced to six weeks in jail on Dec 3 after 171 SMRT bus drivers went on a strike in Singapore on Nov 26. Four Chinese drivers charged last week will be sentenced on Thursday, and 29 others involved in the industrial action have already been deported to China.

The case of the alleged "illegal strike" shows that Chinese migrant workers in Singapore are discriminated against.

Singapore is a civilized state and is widely considered to be a diverse society where the rule of law prevails.

But the strike and the way the local authorities treated the Chinese drivers make one wonder what the real problem is. How does Singapore balance collective interests and individual human rights? Can it regard and treat everyone equally?

The incident reveals that Chinese migrant workers are excluded from salary increments. A recent SMRT salary increment notice stated explicitly that workers "except PRC service leaders" would be eligible for pay rise. This is blatant discrimination. Chinese workers in Singapore work as hard as others - about 10 hours a day, six days a week - but are not paid equal salaries, denied normal increments and don't enjoy good living conditions. This is against the city-state's labor standards.

Even after the strike, the SMRT announced it would not raise the salaries of bus drivers from China beyond 25 Singapore dollars that was announced last week. Its chief executive Desmond Kuek was even quoted as saying that the "increment", compared with Malaysian drivers, was "fair and equitable".

The SMRT's bullish attitude shows that it discriminates against migrant workers not only from China, but also other countries.

We know non-discrimination is the first principle of human rights law. Singapore is a modern state, which supports human rights and the rule of law. So if its laws cannot guarantee the basic principle of human rights, it is setting a rather bad example.

The Singaporean government in 2010 ratified the International Labour Organization's International Labour Standards Convention No. 144, which is about tripartite consultation. We hope the convention is able to help protect the rights and interests of workers, including migrant workers, in Singapore.

Some people are known to exclaim that Singapore has not witnessed a strike for 26 years. Does it mean workers' interests and rights have been sacrificed for 26 years?

While sentencing driver Bao Fengshan, the judge said the verdict should be a warning to others. Singapore cannot sacrifice the rights of its workers to maintain its "no-strike record". The legal remedies for workers in Singapore may be limited and not effective, but the calm response of the Chinese workers has invited highly disproportionate punishment.

Even according to some Singapore media reports, "nearly 80 percent of Singaporeans" felt that SMRT should "bear some responsibility for not managing the grievances of its bus drivers."

Singapore is a country with only 3.77 million natives, which has benefited greatly from the contributions of 1.31 million migrant workers from various countries. A debate has been continuing for long in the country on how to treat migrant workers. But one thing is for sure that migrant workers in Singapore deserve better treatment, at least a treatment that matches the hard work they put in.

The Singaporean authorities, companies and the public have a lot to learn from this case. But more than that, Chinese workers who seek to work abroad should learn more about the country they go to and know how to get legal aid when they face problems.

The Chinese government now pays special attention to protection of Chinese citizens abroad. The Foreign Ministry and the Ministry of Commerce have expressed concerns over the strike incident, and the Chinese embassy in Singapore has communicated with the Singaporean authorities and workers.

The recent Report of the 18th Party Congress said: "We will take solid steps to promote public diplomacy as well as people-to-people and cultural exchanges, and protect China's legitimate rights and interests overseas." This case has highlighted the need for the government to take all necessary steps to protect the rights and interests of Chinese citizens working overseas.

The author is a professor at the Institute of International Law, affiliated to the Chinese Academy of Social Sciences.