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Updated: Jul 31, 2021


Mistake of law and mistake of fact : Sns. 76 and 79.

One of the cardinal rules of criminal law is ignorantia facti excusat, ignorantia juris non excusat (Ignorance of fact is an excuse but not Ignorance of law). This rule is contained in Sns. 76 and 79. According to Sn. 76, a person who believes himself to be bound by law, is excused if he does an act under mistake of fact but not under mistake of law. '

E.g. (i) 'A' a soldier fires on a mob by the orders of the Superior officers as per law. A is not guilty.

(ii) A, a police officer, arrests Z, believing, in good faith that he is the person required. He is not guilty. 'Mistake' is a slip made not by design but by mischance. It is an error that results from unintentional act or omission. Hence, mistake of fact is considered a good defence.

The leading cases are :

1. R.V. Tolson

2. R.V. Prince

In R.V. Tolson, Mrs. Tolson was charged with Bigamy as she had married her a icond husband. Her defense was that Mr. Tolson, her first husband could not be traced for over seven years despite all reasonable means to search adopted. There was not mens rea. Hence, it was held that she was not guilty. 'Mistake of the fact is an excuse' the court declared.

In R.V. Prince, the accused was charged with kidnaping, Annie Phillips, a girl under 16 years of age. The plea of the accused that the girl looked to be above 16, was rejected by the court and he was held guilty. His reasonable belief as to her age was no legal defence.

According to Sn. 79, an act done by a person, who believes himself to be justified by law is excused. However, ignorance of law is no excuse but mistake of fact in good faith is an excuse.

(i) A, a police officer sees Z commit an offence which appears to be murder. A, in good faith, exercising his powers under Cr. P.C. arrests Z. It turns out that there was no murder. Held,, Z not guilty as he is justified by Saw.

(ii) A. a police constable, saw B carrying, three pieces of cloth, suspected them to be stolen and questioned him. B gave no satisfac- tory answers". Hence, he arrested him, but the Inspector released him. B prosecuted the constable for wrongful confinement. Held, consta- ble not guilty. There was a mistake of fact.- Constable was justified by law to enquire B.

In Chirangi V. State, accused in "delusion" took his son as tiger and killed him.. He was protected under Sn. 79.

In State of Orissa V. Ram Bahadur, killing a person as ghost was excused in the set of circumstances of the case

Drunkenness or Intoxication: Sn. 85.

One of the rules contained in the general exceptions of the I.P.C. is that intoxication is a good defence only in a particular circumstance, i.e., when it is not voluntary. Sn. 85 provides that it would be no offense, if the accused at the time of doing it was, by reason of intoxication

(i) incapable of know- ing the nature of the act or

(ii) that what he was doing was either wrong or contrary to law.

The essential condition for excuse is that the thing which caused intoxication must have been administered to him without his knowl- edge or against his will.Drunkenness is a species of madness for which the madman alone is to be blamed.

Case : Director of Public Prosecution V. Beard.

In this case the accused ravished a girl of 13 years of age and in committing rape he placed his hand on her mouth and his thumb on' her throat. The girl died due to suffocation. The plea of drunkenness was rejected. Held, guilty of murder .

Drunkenness in generally not a defence.

The Supreme Court in Vasudev V. State of Persu has laid down conditions. Accused, drunk heavily in a wedding party killed a boy. Held, he was not so much obscured by drink. Held guilty

"Act done in good faith" :

The l.P.C. in the general exceptions Sns. 89, 89, 92 and 93 has provided for certain classes of cases, where there would be no offence, if the "act is done in good faith". This gives protection to the medical profession in particular and to others in general.

(i) If A causes any harm to B, without any intention to cause death, but in good faith, he is not guilty, if B has given his consent to take the harm or the risk (Sn. 88).

E.g. A, surgeon conducts an operation on B (who was suffer- ing from acute stomach pain) with his consent and in good faith to save him. B dies. A has committed no offence. (Sn. 89).

(ii) If A, causes any harm in good faith to B, who is under 12 years of age, or of unsound mind with the consent of the guardian, for the benefit of B. A has committed no offence. (Sn. 89).

A, a surgeon conducts an operation on B, a child of 10 years in good faith to save the child, with the consent of B's father, but the child dies. A has committed no offence.

(iii ) If A causes any harm to B, in good faith for the benefit of B, under such circumstances that consent could not be taken, then, A has committed no offence.

E.g. (a) A, a surgeon sees a child involved in an accident and conducts an emergency operation. There was no time to seek the parents consent.If the child dies, the surgeon has committed no offence

b) A is carried off by a tiger. B shoots at the tiger in good faith to save A, but kills A. B is saved under this section.

(iv) Any communication made in good faith to a person to benefit him is not an offence, if any harm results from it. A. surgeon in good faith tells B. his patient, that in his opinion B would not survive, B dies out of shock. If A,has said this for the benefit of B. A has committed no offence.

The Right of Private defence : (Sns. 96 to 106) :

One of the fundamental principles of law is that every individual has a right to defend himself and his property. This is the doctrine of self-defence or self-preservation. Sns. 96 to 106 have recognised this rule and have provided for the limits within which it may be exercised. This may be discussed under two heads:

  • Right of person

  • Right of property.

  • Right of person :

(i) Every person has a right to defend his own body and the body of any other person against any person. Sn 97

(ii) Against a madman etc: The right extends in all circumstances against any person who is insane, drunk or who by reason of youth immaturity is excused under law[ Sn 98 I P C ] Z under madness attempts to kill A. A may defend and even kill Z if circumstances so warrant.

(iii) Extension of the right: Sn. 100 provides as follows : A person who is under a reasonable apprehension that his life is in danger, may to defend himself, voluntarily cause the death of the assailant if:

a) The assault done by him i .e, assailant causes reasonable apprehension of

1) death or

2) grievous hurt.

b) Or has assaulted with an intention to commit.-

i) The offence of rape

ii) The offence of unnatural lust

iii ) Kidnapping or abduction or

iv) Wrongful confinement, in such circumstances that the defender could not have recourse to public authorities to claim protection.This section empowers n person to defend himself by inflicting injury not greater than what is reasonably necessary. The injury caused in defending must be proportional to and commensurate with the injury received. This is the test.

(v) Only in the above circumstances, the right extends to caus- ing death as recourse. But, in all other circumstances, the right ex- tends to causing any injury other than causing death. (Sn. 101).

In R.V. Rose, H was cutting the throat of his wife, W.Their son saw this and fired at H. H died in consequence. Held, accused is within the limits of private defence. Hence, not guilty.

In Shaku V Crown, H used force to take away his wife W by force from her father's house. W inflicted injuries to H. H died. Held under the circumstances, W was within her right of defence.

iv) Duration : Sn. 102 the right of private defence commences as soon as there is a reasonable fear of danger to the body and continues as long as such fear continues. In Deo Narain V. St. of U. P. the Supreme Court has laid down the meaning of "Duration".

Exception :

(i) There is no right of private defence against a public servant, if he acts in good faith, under colour of his office, though that act may not be strictly according to law. However, if this act causes fear of instant death of grievous hurt, there is a right of private defence There could have been no recourse to any public authorities. No more harm than is necessary to defend, may be inflicted.(Sn. 99)

i i) There is no right of self-defence if the public servant states the authority under which he is acting or produces (Warrant etc.) the same when demanded.

Leading cases

i) St. of U. P. V. Ram swamp

ii) Kishan V, St. of .M.P

iii) Munshi Ram V. Delhi Private defence of property :

i) Every person has a right to defend his property, moveable or immoveable. It may be his own or any person's property. The act of the offender must amount to theft, robbery, mischief, criminal trespass or attempt thereof (Sn. 98).

ii), Extent: The right extends to cause death or any other harm to the offender in the following cases:

a) House-breaking by night.

b) Mischief by fire on any building or vessel.

c) Theft, mischief or house-trespass with a fear that the offender would cause death or grievous hurt, if not defended. This is the test adopted (Sn. 103).

iii) Duration : Sn. 105 The right of private defence commences when there is a reasonable apprehension of danger to property and continues as long as that danger continues. The danger may be due to theft, criminal trespass, mischief or robbery, or house-breaking by night.

(a) In R.V. Halloway Cases : S, the servant of M, saw a boy B, stealing wood. He tied the boy to a horse's tail and beat him. The horse took fright and B died. Held, no private defense, but a case of murder by S.

b) In R.V. Karim Bux, K saw a thief A, entering the house at night through an aperture in the side-wall. K held down the head of A to prevent him from further entering. A died of suffocation.Held, K not guilty.


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