If any person while defending his/her property from robbers, thieves, dacoits, trespassers, commit any harm to the attackers, s/he will not be liable for that offence. But, there are some limitations on the right of private defence.
To understand the law and limitations, it is necessary to consider following laws on it.
Why does law allow to harm any person in defence of property?
In a well-ordered civilised society it is generally assumed that the State would take care of the persons and properties of individual citizens and that normally it is the function of the State to afford protection to such persons and their properties. This, however, does not mean that a person suddenly called upon to face an assault must run away and thus protect himself, He is entitled to resist the attack and defend himself. The same is the position if he has to meet an attack on his property.
In other words, where an individual citizen or his property is faced with a danger and immediate aid from the State machinery is not readily available, the individual citizen is entitled to protect himself and his property.
The exercise of the right of private defence must never be vindictive or malicious.
Law relating to right of defence of property- Section 97
The law relating to defence of property is, set out in s. 97 IPC, which says that every person has a right, to defend-
First-his own body, and the body of any other person, against any offence affecting the human body;
Secondly. -the property, whether movable or immovable, of himself or of any other person, against any act which is an offence falling under the definition of theft, robbery, mischief. or criminal trespass, or which is an attempt to commit theft, robbery, mischief or criminal trespass.
Limitation on the right of private defence
Section 99 of the Code lays down that there is no right of private defence in cases in which there is time to have recourse to the protection of the public authorities.
It further lays down that the right of private defence in no case extends to the inflicting of more harm than it is necessary to inflict for the purpose of defence.
Psychological elements while deciding the offence
There can be no doubt that in judging the conduct of a person who proves that he had a right of private defence, allowance has necessarily to be made for his feelings at the relevant time.
If he faces an assault which causes a reasonable apprehension of death or grievous hurt and that inevitably creates in his mind some excitement and confusion. At such a moment, the uppermost feeling in his mind would be toward off the danger and to save himself or his property, and so, he would naturally be anxious to strike a decisive blow in exercise of his right.
How much force a person can use in defence of property?
To begin with, the person exercising a right of private defence must consider whether the threat to his person or his property is real and immediate. If he reaches the conclusion reasonably that the threat is immediate and real, he is entitled to exercise his right.
In the exercise of his right, he must use force necessary for the purpose and he must stop using the force as soon as the threat has disappeared.
So long as the threat lasts and the right of private defence can be legitimately exercised.
Where a trespasser enters upon the land of another, the person in whom the rightful possession is vested, while the trespasser is in the process of acquiring possession, may turn the trespasser out of the land by force and if in doing so, he inflicts such injuries on the trespasser as are warranted by the situation, he commits no offence.
- Jai Dev vs The State Of Punjab (1963 AIR 612, 1962 SCR (3) 489)
- Munshi Ram And Others vs Delhi Administration, 1968 AIR 702, 1968 SCR (2) 408
 Horam and others v. Rex 50 Cr. L.J. 868