In which of the following case the supreme court has declared S. 303 of IPC as unconstitutional?

The Honorable court held that Section 303 of Penal Code violates the guarantee of equality contained in Article 14 as also the right conferred by Article 21 of the Constitution that “no person shall be deprived of his life or personal liberty except according to procedure established by law”. The clause was initially intended to prevent life imprisonment prisoners from attacking prison employees, but the Legislature picked language that went well beyond that goal. In Machhi Singh v.State of Punjab (1983), the Court elucidated the doctrine of 'rarest of rare.'