What prompted Mayawati to play the Dalit card and support justice Dinakaran?

Uttar Pradesh chief minister Mayawati wrote a letter to prime minister Manmohan Singh on December 20, seeking his intervention to ensure Karnataka high court chief justice PD Dinakaran gets an opportunity to present his point of view before impeachment proceedings begin against him. Many Congress Dalit leaders have also expressed support for him, as has the BJP.

Justice Dinakaran, who faces charges of amassing disproportionate assets and land grabbing, faces an impeachment motion admitted against him in the Rajya Sabha.

Usually, when a person in high office is charged with corruption, public figures, particularly politicians, distance themselves in a bid to escape the negative fallout.

However, Dinakaran's case is made unique by the fact that he is a judge — in India the judiciary is considered the most sacrosanct of institutions — and a Dalit.

Is Mayawati interested in Dinakaran only as a fellow Dalit? Is there more to this than meets the eye?