Preventive action of the police

1. Prevention and investigation

The police have two functions in criminal procedure. One is to investigate offences already committed (Chapter XIII, from section 173). The other is to prevent offences before they happen. Chapter XII, sections 168 to 172 of the BNSS (formerly sections 149 to 152 of the CrPC), deals with the second. It sits beside other preventive provisions: security for keeping the peace and good behaviour (Chapter IX, sections 125 to 143) and public order and nuisances (Chapter XI).

2. Duty to prevent cognizable offences: section 168 (old section 149)

“Every police officer may interpose for the purpose of preventing, and shall, to the best of his ability, prevent, the commission of any cognizable offence.” Interposing is a power; preventing is a duty. The duty is limited to cognizable offences, those for which the police may arrest without warrant. An officer who stands by while a cognizable offence is committed in his presence fails in a statutory duty.

3. Passing on information: section 169 (old section 150)

A police officer who receives information of a design to commit a cognizable offence must communicate it to his superior officer and to any other officer whose duty it is to prevent or take cognizance of it. This keeps intelligence moving up the chain so that preventive action can be taken in time.

4. Preventive arrest: section 170 (old section 151)

Section 170(1). A police officer knowing of a design to commit a cognizable offence may arrest the person so designing, without orders from a Magistrate and without a warrant, if it appears to him that the commission of the offence cannot be otherwise prevented.

Two conditions must both be satisfied:

• the officer must know of a design to commit a cognizable offence, not merely suspect that someone might cause trouble; and
• it must appear to him that the offence cannot be prevented otherwise than by arrest. If a warning, police presence or removal of the weapon would do, arrest is not justified.

Section 170(2). The person arrested shall not be detained for more than twenty-four hours from the arrest, unless further detention is required or authorised by another provision of the Sanhita or any other law (for example, an order under the security proceedings in Chapter IX, or a preventive detention order).

In Ahmed Noormohmed Bhatti v. State of Gujarat, 2005 INSC 144, (2005) 3 SCC 647, the Supreme Court upheld the old section 151 against a challenge under Articles 21 and 22. Its object is to prevent the commission of cognizable offences, and the conditions in the section are safeguards against misuse. A police officer who arrests under it without the required knowledge, or detains beyond the time permitted, acts outside the section and may be proceeded against.

The safeguards that apply to every arrest also apply here: the grounds must be communicated (section 47), the arrested person must be produced before a Magistrate within twenty-four hours (section 58 and Article 22(2)), and a relative or friend must be informed (section 48).

5. Protection of public property: section 171 (old section 152)

A police officer may, on his own authority, interpose to prevent any injury attempted in his view to any public property, movable or immovable, or the removal or injury of any public landmark, buoy or other mark used for navigation.

6. Duty to obey lawful directions: section 172 (new)

• All persons are bound to conform to the lawful directions of a police officer given in fulfilment of any of his duties under this Chapter (section 172(1)).
• A police officer may detain or remove any person resisting, refusing, ignoring or disregarding such a direction, and either take him before a Magistrate or, in petty cases, release him as soon as possible within twenty-four hours (section 172(2)).

The old Code had no such provision. It gives the police power to clear a crowd or remove an obstructing person while preventing an offence. Critics point out that “ignoring or disregarding” is wide and could be used against peaceful protesters, so the direction must itself be lawful and connected with the duty to prevent a cognizable offence; otherwise the detention is illegal.

7. Problem: the threatened clash

The police learn that X has gathered men and weapons to attack a rival group at a temple festival that evening. The inspector arrests X at noon and keeps him in the lock-up for three days without producing him before a Magistrate. Discuss.

Issue. Whether the arrest and the detention are lawful.

Law. Section 170(1) permits arrest without warrant of a person known to have a design to commit a cognizable offence, if the offence cannot otherwise be prevented. Section 170(2) limits detention to twenty-four hours unless another law authorises more. Article 22(2) and section 58 require production before a Magistrate within twenty-four hours.

Application. An armed attack is a cognizable offence (rioting, attempt to murder). The police had specific information, and with the attack set for that evening an arrest may well have been the only way to prevent it. The arrest is therefore justified. But keeping X for three days without production breaches section 170(2) and Article 22(2).

Conclusion. The arrest was lawful; the detention after twenty-four hours was illegal. X may seek release by habeas corpus and claim compensation for the illegal detention, and the officer is liable to departmental and criminal action.

How this is examined

A 6-mark short note in June 2025. Write sections 168 to 172 in order, explain the two conditions in section 170 and the 24-hour limit, cite Ahmed Noormohmed Bhatti, and mention that section 172 is new. A preventive arrest problem can be solved with the same material.