Ullmann v. United States, 350 U.S. 422 (1956), was a United States Supreme Court case in which the court held that a person given immunity from prosecution loses their Fifth Amendment right against self-incrimination, thus upholding the Constitutionality of the Immunity Act of 1954. The Court stated, "This command of the Fifth Amendment ('nor shall any person . . . be compelled in any criminal case to be a witness against himself. . . .') registers an important advance in the development of our liberty — 'one of the great landmarks in man's struggle to make himself civilized.'"