Why is police brutality so common in India?
I have had several interactions with police in India, and none were pleasant. Why?
1) Stanford Prisoner Experiment
Given someone power over other people, and lack of oversight, sadism and abuse of privilege won't be far away.

2) Lack of reforms
Our laws are a hotch-potch, some were drafted in the mid 1800s and some a month back. Several laws are contradictory too.There have been several committees for reforming the Indian Police Service, and almost none of their recommendations have been implemented.

3) Police:Population Ratio
India currently has 130 police officers per 100,000 people. That is low. This concentrates power in the hands of a few.

4)Slow and Overburdened Judicial system
It takes years to move cases through courts. And an ongoing case can destroy your reputation and make you lose your job, family etc. There is almost no recourse in India to suing for damages. So you shut up, and pay the bribes. Unscrupulous police know this and prey on it.

5)Us
Is reform ever an election plank? Do we ever demand it? If we know it's bad, and do nothing to change it, we are guilty too.