Indian Penal Code, 1860
6. Definitions in the Code to be understood subject to exceptions
Throughout this Code every definition of an offence, every penal provision, and every illustration of every such definition or penal provision, shall be understood subject to the exceptions contained in the Chapter entitled "General Exceptions", though these exceptions are not repeated in such definition, penal provision, or illustration.
(a) The sections, in this Code, which contain definitions of offences, do not express that a child under seven years of age cannot commit such offences, but the definitions are to be understood subject to the general exception which provides that nothing shall be an offence which is done by a child under seven years of age.
(b) A, a police-officer, without warrant, apprehends Z, who has committed murder. Here A is not guilty of the offence of wrongful confinement for he was bound by law to apprehend Z and therefore the case falls within the general exception which provides that "nothing is an offence which is done by a person who is bound by law to do it".