Generally, Section 105 of the Evidence Act 1950 stipulates that when a person is accused of any offence, the burden of proving that such offence committed is within any exception is to be on the shoulder of the accused. The court shall presume that no exception can defend the accused unless and until the accused prove to the court that such defence or exception does exist when the offence was committed.
Now, one of the available defences is the defence of mistake provided under Section 76 of the Penal Code. This proviso is to exempt a person from any conviction in these two circumstances. First, when a person does an act which he is bound to do it as provided in illustration (a) of the provision. Second, is when a person does an act by a reason of a mistake of fact in good faith believing himself to be bound by law to do it as accorded in illustration (b) of the provision. This proviso basically encompasses a criminal act that has been committed with an absence of mens rea (intention to commit the offence) which will cause the person to not be liable.
The basic examples narrated below will show how the defence of mistake works:
1. A hit B, which has caused B to have injuries. When A is charged for assault, he cannot raise the defence that he did not know that hitting and causing hurt to a person is an offence and pleads defence of mistake. This type of defence cannot be accepted because every person is presumed to know the law of the land. Hence, a person cannot be exempted from a liability of an offence on the ground that he is ignorant of the law.
2. In the case of Chirangi v State of Nagpur  Nagpur 282, the appellant was suffering from bilateral cataract which has caused him to mistake his son for a tiger and has murdered his own son and not the tiger. There was also evidence tendered in court to show that the abscess in the appellant’s leg had produced a certain temperature which has caused a temporary delirium to the appellant. Such temporary delirium might have created a secondary delusion that magnified the image created due to the defect of the appellant’s vision. As such, the appellant was charged for murder under Section 302 of the Indian Penal Code. In this case, the court held that the evidence clearly showed that the appellant’s with his existing physical ailments would have produced a state of mind; that he has acted in good faith and he thought that he was attacking a tiger with his axe instead of his son. Thus, the appellant’s conduct was manifested to have no intention of murdering his son.
Here, he was protected by the defence of mistake under Section 79 of the Indian Penal which provides that nothing is an offence if it is done by any person who by reason of a mistake of fact and has acted in a good faith, believing himself to be justified by law in doing such act.
It must be understood that this defence does not give an accused full privilege to act without restriction. In this instance, the conduct of the accused must be necessary to protect or further the interest at stake. It also places limit on the maximum harm that is proportionate and reasonable that may be used in protection or furtherance of such interest. Similarly, it reflects the disability or any abnormal condition of the accused during the material time the offence is committed. For example, if the accused is suffering from any abnormality and the like, it does not only require an element of disability on the part of the accused to be satisfied, but it also requires that such disability would definitely cause a particular result, as clearly discussed in the Chirangi’s case.
Author: Nur Farihah Binti Syahriza, Pelatih Dalam Kamar.