Thus, for instance, under Schedule I of the Code, the following are examples of offences under the Indian Penal Code which are cognizable offences:
S. 121: Waging war against the Government of India
S. 124: Assaulting the President of India or the Governor of a State, with intent to compel or restrain the exercise of any lawful power
S. 302: Murder
S. 304: Culpable homicide not amounting to murder
S. 304-A: Causing death by rash or negligent act
S. 304-B: Causing dowry death
S. 379: Theft
S. 384: Extortion.
On the other hand, under Schedule I, the following are instances of offences under the Indian Penal Code which are classified as non- cognizable:
S. 168: Public officer unlawfully engaging in any trade
S. 172: Absconding to avoid service of summons
S. 177: Knowingly furnishing false information to a public servant
S.186: Obstructing a public servant in discharge of his public functions
S. 278: Making atmosphere obnoxious to health
S. 494-A: Keeping a lottery office
S. 426: Mischief
T. 477-A: Falsification of accounts.
Similarly, a cognizable case is a case in which a Police Officer may arrest without a warrant, and a non-cognizable case is one in which a Police Officer has no authority to do so.
Sometimes, a single case may include several offences. If all the offences are non-cognizable, it is a non-cognizable case. If, however, one or more of the offences is cognizable, it would be cognizable case. In other words, a case cannot be partly cognizable and partly non- cognizable. (V.K. Rao, AIR 1961 A.P. 448)
It may be noted that the test is not whether in fact the arrest is effected without a warrant, but whether it can be so effected. However, if under the Code, a Police Officer can arrest without a warrant only if the offence is committed in his presence, it is not a cognizable offence.
The term cognizable offence also covers cases where under any other law in force, a Police Officer can arrest without a warrant. Examples of cognizable offences of this type are to be found in the Railway Act, 1890 and the Police Act, 1861.
If, however, the offence is one which is non-cognizable, a Police Officer cannot investigate into it without the authority of a Magistrate under S. 155(2); nor can he make a search under S. 165.
The following are the main provisions of the Code in connection with cognizable offences:
(i) Any Police Officer may, without a warrant, arrest any person concerned in a cognizable offence, or against whom a complaint has been made, or information received or suspicion exists, that he has been concerned in a cognizable offence. (S. 41)
(ii) So also, every Police Officer can interpose for preventing the commission of a cognizable offence. (S. 149)
(iii) On receiving information of a design to commit such an offence, a Police Officer must communicate it to his superior officer, and to any other Officer whose duty it is to prevent or take cognizance of its commission. (S. 150) He may also arrest the person so designing without a warrant, if the offence cannot be otherwise prevented. (S. 151)
(iv) If information of a cognizable offence is given orally to the Police Officer, he must cause it to be (i) reduced in writing, (ii) read over to the informant, (iii) signed by him, and (iv) the substance thereof entered in a prescribed book (known as Station House Register or Station Diary). If given in writing, the information must be signed by the informant, and the substance thereof entered in the prescribed book. (S. 154)
(v) If a Police Officer has reason to suspect the commission of a cognizable offence, he must forthwith send a report of the same to a competent Magistrate, and must proceed to investigate the facts and circumstances of the case, and if necessary, take measures for the discovery and arrest of the offender (S. 157). On receiving such a report, the Magistrate may (a) direct investigation, or (b) proceed to hold a preliminary inquiry, or depute any subordinate Magistrate to do so, or (c) otherwise dispose of the case. (S. 159)