Your case appears to be from Tamil Nadu, since Section 292-A IPC appears to be applicable only in Tamil Nadu through a state amendment.
Since in your case, the FIR is already filed and investigation is going on, you should cooperate with the investigation and provide whatever evidence is available to the police. You may also keep record of the evidence (such as, posters displayed in village), in case needed in future; you may take photographs of such posters. If you feel that the investigation is not being conducted properly, intervention of the senior officers may be helpful and for this purpose, you can try to convince the senior officers.
After the completion of investigation, if the police closes the case and does not charge sheet the accused (or if the police files a charge sheet, but does not apply proper sections), you’ll get a chance to file your protest petition before the Magistrate court. At that time, you may show the relevant evidence and convince the Magistrate court to take cognizance of the case under proper sections, despite a police report to the contrary. If needed, at that time, you can pursue the case as a private complaint case, in which scenario, you have to prove the case yourself (or by your private lawyer) by providing sufficient evidence.
You also have the option of approaching the high court for directing the police for proper investigation, but the chances of the high court intervening are generally very less.
Dr. Ashok Dhamija is a New Delhi based Supreme Court Advocate and author of law books. Read more about him by clicking here. List of his Forum Replies. List of his other articles. List of his Quora Answers. List of his YouTube Videos.