The powers given to the police under these sections are as follows:
(1) Every police officer may interpose for the purpose of preventing the commission of a cognizable offence, i.e., an offence for which he could arrest without a warrant. (Section 149)
On receiving information of a design to commit any cognizable offence, the police officer has to communicate such information to his superior officer and to any other officer whose duty it is to prevent or take cognizance of the commission of any such offence. (Section 150)
A police officer knowing of a design to commit any cognizable offence may arrest, without orders from a Magistrate and without a warrant, the person so designing, if it appears to him that a commission of the offence cannot be otherwise prevented. (Section 151)
(2) A police officer may, of his own authority interpose to prevent any injury attempted to be committed in his view to any public property, movable or immovable, or the removal of or injury to any public landmark or boy or other mark used for navigation. (Section 152). The essential condition is that the attempt must be made in view of the police officer.
(3) An officer in charge of a police station may without a warrant enter any place within the limits of such station for the purpose of inspecting or searching for any false weights or measures or instruments for weighing. If he finds in such place any false weights, measures or instruments for weighing, he may seize the same and report the seizure to a Magistrate having jurisdiction. (Section 153)