(1) Whoever voluntarily causes hurt to any person being a public servant in the discharge of his duty as such public servant, or with intent to prevent or deter that person or any other public servant from discharging his duty as such public servant or in consequence of anything done or attempted to be done by that person in the lawful discharge of his duty as such public servant, shall be punished with imprisonment of either description for a term which may extend to five years, or with fine, or with both.
(2) Whoever voluntarily causes grievous hurt to any person being a public servant in the discharge of his duty as such public servant, or with intent to prevent or deter that person or any other public servant from discharging his duty as such public servant or in consequence of anything done or attempted to be done by that person in the lawful discharge of his duty as such public servant, shall be punished with imprisonment of either description for a term which shall not be less than one year but which may extend to ten years, and shall also be liable to fine.
Legal Commentary & Landmark Judgments: Section 121
Section 121 penalizes voluntarily causing hurt or grievous hurt to deter a public servant from the discharge of his duty, prescribing imprisonment up to five years for hurt, and imprisonment of not less than one year extending up to ten years for grievous hurt.
In defending citizens charged with assaulting police or municipal demolition squads, cross-examine on the legality of the official action: if the officer was acting without jurisdiction, off-duty, or committing an illegal assault, Section 121 BNS cannot be sustained.