Brahmins have been guilty of various wrong actions, as have all classes and groups in India. This occurred mainly when Brahmins failed to act like true Brahmins, that is as selfless teachers, but instead took to worldly goals. But actual instances of Brahmins perpetrating violence against other groups were very rare. Most of the higher caste-lower caste violence in India does not involve Brahmins but other wealthier caste groups. 

No history exists of the kind of massacres of people done by Brahmins as done by Muslim armies, who killed Hindus in the tens of thousands (including many Brahmins), or the kind of economic exploitation as perpetrated by the British, who drained the wealth of the subcontinent. No such religious intimidation exists by Brahmins as the Muslims and Christians implemented in India in their attempts to force conversion of Hindus.