131. Whoever assaults or uses criminal force to any person otherwise than on grave and sudden provocation given by that person, shall be punished with imprisonment of either description for a term which may extend to three months, or with fine which may extend to one thousand rupees, or with both.
Explanation 1.-Grave and sudden provocation will not mitigate the punishment for an offence under this section,-
(a) if the provocation is sought or voluntarily provoked by the offender as an excuse for the offence; or
(b) if the provocation is given by anything done in obedience to the law, or by a public servant, in the lawful exercise of the powers of such public servant; or
(c) if the provocation is given by anything done in the lawful exercise of the right of private defence.
Explanation 2.-Whether the provocation was grave and sudden enough to mitigate the offence, is a question of fact.