"Accident", a word which is used in everyday life to indicate a course of events over which a person had no control over and which could not be avoided despite due diligence and care. Section 80 talks about accident as a general exception and which can lead to avoidance of criminal punishment and liability if established fully before a court of law. Law does not intend to punish a man of the things over which he could possibly have no control over.  Actus non facit reum nisi mens sit rea only works as a reminder that criminal law in order to punish seeks some kind of guilty mental element to punish a person. This implies that a person when does not intend and cannot even contemplate occurrence of a certain course of events, cannot be held responsible for the happening of that event.

Essentials
Nothing is an offence
When studying chapter IV which talks of general exceptions, the phrase "nothing is an offence" appears frequently. This phrase has to be read with section 6 of the Indian Penal Code which says that the offences be read subject to general exceptions as given under chapter IV. Hence, the phrase elucidates that when a particular situation falls under section 80 and satisfies the ingredients given it will not be an offence.

Done by accident or misfortune
Accident comes from the word accidere which means to happen or befall upon, whenever we use this term in daily life it usually reflects a course of events out of our control. As they say "Accidents happen", this indicates the core of this general exception that there was no fault of a party which led to the unwanted consequence. The second term used i.e "Misfortune" is synonymous with bad luck or an event which was undesirable. Misfortunes are similar to accidents but with the only difference that accidents result in harm to others but misfortune may also result in harm to the doer.

Without any criminal intention or knowledge
Criminal intention or knowledge as reflected in the second constituent of crime under criminal law i.e "Mens rea" is one of the vital part which is necessary to make an individual liable for his acts. Intention is when the accused brings about the very result which it was his purpose to bring about, he is said to have acted intentionally. In criminal jurisprudence it is presumed that a man intends the natural consequences of his act. Knowledge on the other hand means an acquaintance with the fact or the truth pertaining to a certain event, it involves awareness of a fact, belief or mental impression and many offences under the IPC make "knowingly" doing of an act as punishable. Accidents and misfortunes by their very nature negate the presence of a criminal intention or knowledge and on this ground the accused may be excused from criminal liability. In State of M.P. v. Rangaswamy AIR 1952 Nag. 268, accused though that he’d seen a hyena 152 feet away and shot at its direction. But later on it was found out that it was a person, he pleaded that it was raining and had a bonafide impression that it was a hyena and he in order to protect the people around him fired the shot. Court held that he will be entitled to the benefit under section 80 as besides the other facts, there was no expectation of any other person being present in the area where the shot was fired which resulted in the death of a human being.

Lawful act in a lawful manner by lawful means
It is important that the act which was being done was lawful, in a lawful manner and by lawful means. As in Tunda v. Rex (skip to relevant cases part for brief story) , besides the defence of section 87(consent), section 80’s benefit was also given due to the fact that there was no foul play by the deceased and both friends impliedly agreed to accidental injuries while going for a wrestling bout with each other. A woman who in order to discipline her child, hits him with an iron rod but the rod hits another child and causes injury will not be entitled to the defence of accident as the act itself lacks lawfulness and cannot be said to be in a lawful manner and by lawful means.

With proper care and caution – Act done without any regard to proper care and caution also come within the purview of mens rea as they come under the concept of negative mens rea. Offences such as criminal negligence have this negative mens rea imbibed in them. In these cases a person does an act with total disregard to the consequences which may ensue from such carelessness.

Shankar Narayan Bhadolkar v. State of Maharashtra AIR 2004 SC 1966, this case elucidates the principle that when an act is done deliberately and without proper care and caution, it will not be given the benefit of accident. A host who unlocks his pistol, loads it with cartridges and ends up shooting one of the invitees to a dinner from a close range is certainly an act where proper care and caution was thrown out of the window.
This instance also highlights the problem of "celebratory firing" in marriages, in these cases too, a person will not be given the benefit of accident as firing bullets while attendees are present is certainly not an act done with proper care and caution as there is always the risk of bullet hitting one of the attendees.


Relevant cases
Tunda v. Rex 1950 Cr. Lj. 402 (All. HC)
The accused and the deceased were friends who were wrestling fans and were engaged in a wrestling bout. While wrestling, the deceased’s head accidentally came in contact with a concrete platform resulting in injuries to the skull and eventual death. The accused was tried under section 304 but later on convicted under section 304A. He preferred an appeal to the Allahabad High Court, which held that when the accused and deceased agree to wrestle with each other, there was an implied consent on each part to suffer any accidental injuries. The injury was accidental and there was no foul play on part of the accused and hence is to be given the benefit under section 80 and section 87.

Bhupendra Sinha Chaudasama v. State of Gujarat 1998 Cri.LJ 57
Where the accused shoots his own colleague at a close range without knowing the identity of the target, this act reflects utter lack of care and caution and hence, the benefit under section 80 will not be available to him.