IPC section 99 Indian Penal Code. IPC 99 is a section of the Indian Penal Code that deals with the acts against which there is no right of private defence. There is no right of private defence against an act which does not reasonably cause the apprehension of death or of grievous hurt, if done, or attempted to be done, by a public servant acting in good faith under colour of his office, though that act may not be strictly justifiable by law. There is no right of private defence in cases in which there is time to have recourse to protection of the public authorities. 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. In simple words, this means that you cannot use force to defend yourself or others against a public servant who is doing his duty, unless you fear for your life or serious injury. You also cannot use force if you have enough time to seek help from the police or other authorities. And you cannot cause more harm than what is needed to stop the attack. You can read more about IPC 99 and its implications from these sources: 1,  2,  3, and 4. I hope this helps you understand IPC 99 .