Section 76 of the IPC states that “ Nothing is an offense which is done by a person who is, or
who by reason of a mistake of fact and not by reason of a mistake of law in good faith believes
himself to be, bound by law to do it.
Section 79 of the IPC states that “ Nothing is an offense which is done by any person who is
justified by law, or who by reason of a mistake of fact and not by reason of a mistake of law in
good faith, believes himself to be justified by law, in doing it.
Both these sections talk about the mistake of fact and mistake of law. The mistake of fact is
excusable whereas the mistake of law is not excusable. Section 76 further talks about “bound
by law” and section 79 talks about “justified by law”.
“Bound by law” means that although the facts show that the offense is committed still the
person under the mistake of fact believes that he was bound by law to act in that particular
way. For instance, if a police officer, arrests a person by the order of his superior officer, he
would be bound by law to act in that way.
“Justified by law” means that the law gives a person the power to act in a particular way. To put
it in simpler terms, it means that the person is empowered by law, the person had sufficient
reasons to act in that way. For instance, X saw Y engaged in inflicting blows on Z. X caught Y in
order to hand him over to the police. But later it was found that Y was exercising his right to
private defense. Here, as X acted in good faith, his act would be justified by law.