Salil Shetty: Apartheid is a continuing reality for India's Dalits

It is now eight years since South Africans voted in a government committed to equal opportunities for all people, rather than different treatment linked to the colour of their skin. But, in India, the world's biggest apartheid system – based on another hereditary factor, caste – remains intact after more than 3,000 years.

How symbolic that the term Dalit, for the lowest caste once called untouchable, is an ancient word defined as ground or broken to pieces. The American scholar, Dr Eleanor Zelliot, elaborates the meaning. She writes that Dalit implies those who have been broken, ground down by those above them in a deliberate and active way.

The Dalits number 167 million of India's billion people. Yet, because of the caste system many are doomed to the harshest conditions from birth. In rural India, they live on the margins of villages, denied access to wells and temples. Dalits are confined to work that most other people reject – labouring and clearing human excrement and animal carcasses. Dalits must not touch or even walk in the shadow of higher-caste people. Repression is rife – assaults, rape, murder and homes set on fire.

The future for new generation of Dalits hardly seems better. Dalit children often receive verbal and physical abuse from teachers and perform less well than others. While many people are gaining from India's economic growth, the boom is leaving the Dalits behind.

Although the constitution includes quotas on fair employment opportunities – almost one in five government posts is supposed to go to a Dalit for example – these principals are clearly ignored when staff are appointed.

Through efforts like this, the Dalits, oppressed for centuries, are increasingly organising to demand access to education, healthcare and jobs.

Those with ultimate authority, accountable to the electorate, must discharge their responsibilities. In India, the largest democracy on earth, the media and judiciary must help enforce the law and constitution to ensure that these basic rights are honoured.

For many activists in the international human rights arena, the Dalits question presents a real dilemma. On the one hand, we are tired of donor conditionalities, which seldom work, imposed on the developing world and the steady erosion of the sovereignty of poor countries. But can the international community silently watch as 200 million Dalits in South Asia are denied their basic human rights?