The Police Complaints Authority (PCA) were to be established at the state and district levels following the judgement by the Supreme Court of India, in the Prakash Singh and Ors. v. Union of India and Ors. AIR 2006 SCC 1 Case, in response to the huge volume of complaints against the police and the endemic lack of accountability.
References
Police Complaints Authority (India) Wikipedia(Text) CC BY-SA