concurring.
I concur in the opinion and judgment of the Court, but would add that substantial federal questions may arise if the petitioner is again called upon to testify concerning bribery on the police force while he was an officer and if he is thereafter denied immunity as to any offenses related to the investigation.
This Court has never held that a State, in the absence of an adequate immunity statute, can punish a witness for contempt for refusing to answer self-incriminatory questions. A case involving such facts has never been presented here.1 Nor is this such a case, since New York, by § 381 of the Penal Law, has granted immunity. Petitioner was obliged to answer the questions as would be any witness in the State of New York. If he had signed no waiver, he concededly would have been compelled to testify, since under § 381 of the New York Penal Law he would be entitled to immunity. The fact that he signed a waiver, even assuming it to be invalid as he claims, certainly cannot relieve him from the duty of every citizen to testify. His failure to so testify, therefore, placed him in contempt of court and subject to the punishment accorded him in this case.
However, because it appears from the record to be the intention of the authorities to punish him both for con*66tempt for refusal to testify and for bribery if he admits such misconduct, we might eventually be faced with the question of what his rights would be if on a subsequent hearing he should incriminate himself after claiming a privilege against self-incrimination. Petitioner might defend against a prosecution stemming from such involuntary testimony by challenging the validity of the waiver, basing his objection on an asserted federal right against self-incrimination. Such a challenge might well embrace the contention made here of coercion in the procurement of the waiver, as well as the claim that its use well beyond the term of petitioner’s public employment would be an unreasonable interference with petitioner’s claimed federal right.2
Moreover, a state immunity statute — like any other state statute — must be applied uniformly unless there is some reasonable ground for classification; otherwise, the Equal Protection Clause of the Fourteenth Amendment is violated.3 After a city employee suffers the primary sanction of the constitutional and charter sections— namely, loss of his position — it may well be that the waiver cannot be used to send him to the penitentiary for bribery when the same sanction would not be imposed on other witnesses giving like testimony.
However, as already noted, we do not reach these questions here.
Compare Twining v. New Jersey, 211 U. S. 78 (jury instruction authorizing the jury in a criminal case to draw an unfavorable inference from the accused’s failure to take the stand); Adamson v. California, 332 U. S. 46 (state law permitting prosecutor and trial judge to comment on the accused’s failure to take the stand); Snyder v. Massachusetts, 291 U. S. 97, 105 (denial of permission to the accused to accompany jury on visit to scene of crime); Palko v. Connecticut, 302 U. S. 319, 325-326 (state statute allowing appeal by State in criminal cases).
Cf. Terral v. Burke Construction Co., 257 U. S. 529.
See, e. g., Dowd v. United States ex rel. Cook, 340 U. S. 206, and Cochran v. Kansas, 316 U. S. 255.