Chamar! Unparliamentary word?

Today Hukum Dev Narayan Yadav raised topic that there should a regiment in name of Chamar caste too. His logic was that there are nine regiments in name of different castes e.g. Rajput, Jat, Gurkha etc. His another point was that in 1942 to fight second world war Chamar regiment was raised. It was dismantled after second world war. So he questioned why it cannot be raised again.
It is very contentious issue. Once a new regiment is made in name of one caste similar voice for another caste will be raised. No government will try to burn its finger in fire. That is separate matter.
The matter of present concern was the comment of then presiding officer Smt. Girija Vyas. Before MP could start his speech he was directed to remove some of the words indicating to castist nature. It gave indication that there was something wrong said about some caste. But when I heard the complete speech there was no humiliating word against any community. During the speech he was told not to use word Chamaar. Then it occurred to me that according to officer word Chamar itself was derogatory in nature.
I know that some of the so called higher caste used to use name of so called lower caste as abusive word. Now that the time is changing and government is giving extra facility to so called lower castes. So on the paper people are encouraged to ascertain their caste. In fact when so called lower caste are being loud in ascertaining this. But at the same time it looks ruling class still considers Chamaar and other similar word as unparliamentary.