As we can see, Inspector Nalawde was involved with releasing Amit and Zafar after the first rape by planning the kidnapping of Rohan and his wife, so they could not have a true report of the rape. And it let to them doing it again.
We see Rohan use Inspector Nalawde's voice to plan Amit's murder. So he knows Inspector Nalawde is protecting Amit and Zafar.
Rohan decided to kill all those who were involved and killed them, except Inspector Nalawde. Why didn't he kill Inspector Nalawde?
Rohan killed Amit and Zafar, who actually raped his wife, yeah... It was straight forward.
Now, Amit's brother (Corporator Shelar). He was not only Supporting his younger sibling's Crime but also after Supriya's death, Shelar visited Rohan's house and told, what his brother did was just right and did this Crime only on the basis of his Power.
And importantly, he was going to kill Rohan after Amit's Murder (or let say, planned suicide ;) So anyhow, Rohan had to kill Corporator Shelar, the bodyguard died accidently.
Now, character Nalawade is an arrogant inspector, such can be seen in almost every custody in India. Nalawade and his senior Inspector is the witness to today's Law and Order in India, who work for Bad people helplessly, just because of fear or desire for better life. In short, his act of releasing Rapists was actually on behalf of Corporator Shelar only!
In short, Society involves:
