What percent violation of human rights is done by police ?

As per the Cases coming to manav adhikar protection organization(MAPO),An organization working against the violation of human rights in India 70% of the cases are against the police.Hence police is playing a leading role in the violation of human rights and harassment of the common people.
The major issue is this Does police is the origin point of the these cruel deeds or......................some other reasons are behind this.like.......politics