False complaint under sc/st act

SC community person lodged under sc/st Act on the instigation of of BC community person who ruling party man also. On preliminary enquiry local police station SI found and convinced that the complaint is false. SI called both parties (after 20 days from datr of complaint) to station to warn and get statement from the complainant. But he did not turn up and using political ifluence silenced the police. Now it is nearly 1.5 months. Complaint neither registered nor closed. I dont have complainte copy. I want to sue the complainant for false complaint. Pls me know how can i do without complaint copy and who is the PIO or APIO in tanilnadu police stations?