Right of Private Defense against the act of a person of unsound mind
Every person has an right of private defence against the act, which would otherwise be certain offence, but is not that offence, by reason of the doer being of unsound mind, a minor, an intoxicated person, or a person acting under a misconception of fact.
For Example: Z, under the influence of madness, attempts to kill B; Z is guilty of no offence. But B has the same of private defence which he would have if Z were sane.
The punishment would depend upon the discretion of the court, which after satisfying itself that there was other option left, than to exercise the right of private defence.