Legal maxim

Ignorantia Fact Excusat means that mistake of a fact is an excuse. It is applicable to civil as well as criminal cases. It means that, if a person can prove that he was unaware of the facts, then his mistake can be excused by the law. If a person has committed a wrongful act without intending for the wrong consequences, he/she will be excluded from the civil or criminal liability. This is allowed as an exception, because in this case, the person committing the wrong doesn’t have enough mens rea.

The Indian Penal Code says that if an offense is committed by someone by mistake of fact, where he/she thinks the action was right according to the law, will not be counted as an offense. Even in the Indian Contract Act, the agreement is said to be void, if both the parties are in mistake of fact about the terms of the agreement.

State of Orrisa v. Khora Ghasi

The accused in this case mistakenly shot a man, while thinking that it was a bear in his field. The Court acquitted the man on the basis of mistake of fact.

Ignorentia Juris Non Excusat means that mistake of law is not an excuse. This means that, if a person does not have knowledge of the fact that an act committed by them is an offence under the law, it does mean that they shall be excused from any consequences that follow. These laws have to be known by a person whether or not he/ she knows the entire fact. An exception to this, is the ignorance of foreign law. Any ignorance of foreign law is treated as an ignorance of fact.

Section 76 and 79, note that any exception from conviction can only occur, if it is done due to the mistake of fact and not due to mistake of law in good faith. In the Indian Contract Act, a party cannot claim relief on the grounds that he was unaware of the Indian Law.

Mohammad Ali v. Sri ram Swarup

In this case, it was held that, mistake of law is not an excuse, even if it is done in good faith. It may act as a deterrent in the punishment, but has nothing to do with acquittal.