The police could not register all of the complaints.
The police have the authority to register F.I.R.s under Section 154 of the Cr.P.C. in cases of cognizable offenses. The investigation will be conducted based on the complaint given, without court approval. If such an offence is committed, the police can also arrest the offender without a warrant.
In non-cognizable offences, the police cannot register the F.I.R. or conduct an investigation without a court order; they also can't arrest the accused without a warrant from the court. In such non-cognizable cases, the complainant has to file a complaint directly with the court and such complaint is generally called “private complaint”.
Sometimes, even in cases of cognizable offenses, the police may refuse to process the FIR based on one or another reason. In such a situation, the complainant may also file the complaint with the court, a process known as "private complaint". In other words, a "private complaint" is one that is directly filed by the complainant with the court. The Magistrate can take cognizance of such a private complaint under Section 190(1)(a) of the Cr.P.C., and the magistrate would direct police to investigate and submit a report .
If a complaint is filed, you will receive a summons from the court