Petitioner was tried and convicted of knowingly transporting a woman in interstate commerce for the purpose of prostitution, in violation of the White Slave Traffic Act, 18 U.S.C. § 2421, 18 U.S.C.A. § 2421. At the trial, the woman, who had since the date of the offense married the petitioner, was ordered, over her objection and that of the petitioner, to testify on behalf of the prosecution.1 The Court of Appeals, on appeal from a judgment of conviction, affirmed the ruling of the District Court. 263 F.2d 304. As the case presented significant issues concerning the scope and nature of the privilege against adverse spousal testimony, treated last Term in Hawkins v. United States, 358 U.S. 74, 79 S.Ct. 136, 3 L.Ed.2d 125, we granted certiorari. 360 U.S. 908, 79 S.Ct. 1299, 3 L.Ed.2d 1259. We affirm the judgment.

First. Our decision in Hawkins established, for the federal courts, the continued validity of the common-law rule of evidence ordinarily permitting a party to exclude the adverse testimony of his or her spouse. However, as that case expressly acknowledged, the common law has long recognized an exception in the case of certain kinds of offenses committed by the party against his spouse. Id., 358 U.S. at page 75, 79 S.Ct. at page 137, citing Stein v. Bowman, 13 Pet. 209, 221, 10 L.Ed. 129. Exploration of the precise breadth of this exception, a matter of some uncertainty, see 8 Wigmore, Evidence (3d ed.), § 2239, can await a case where it is necessary. For present purposes it is enough to note that every Court of Appeals which has considered the specific question now holds that the exception, and not the rule, applies to a Mann Act prosecution, where the defendant's wife was the victim of the offense.2 Such unanimity with respect to a rule of evidence lends weighty credentials to that view.

While this Court has never before decided the question, we now unhesitatingly approve the rule followed in five different Circuits. We need not embark upon an extended consideration of the asserted bases for the spousal privilege (see Hawkins, supra, 358 U.S. at pages 77—78, 79 S.Ct. at pages 138—139; Wigmore, op. cit., supra, § 2228(3)) and an appraisal of the applicability of each here, id., § 2239, for it cannot be seriously argued that one who has committed this 'shameless offense against wifehood,' id., at p. 257, should be permitted to prevent his wife from testifying to the crime by invoking an interest founded on the marital relation or the desire of the law to protect it. Petitioner's attempt to prevent his wife from testifying, by invoking an asserted privilege of his own, was properly rejected.

Second. The witness-wife, however, did not testify willingly, but objected to being questioned by the prosecution, and gave evidence only upon the ruling of the District Court denying her claimed privilege not to testify. We therefore consider the correctness of that ruling.3

The United States argues that, once having held, as we do, that in such a case as this the petitioner's wife could not be prevented from testifying voluntarily, Hawkins establishes that she may be compelled to testify. For, it is said, that case specifically rejected any distinction between voluntary and compelled testimony. 358 U.S. at page 77, 79 S.Ct. at page 138. This argument fails to take account of the setting of our decision in Hawkins. To say that a witness-spouse may be prevented from testifying voluntarily simply means that the party has a privilege to exclude the testimony;4 when, on the other hand, the spouse may not be compelled to testify against her will, it is the witness who is accorded a privilege. In Hawkins, the Government took the position that the spousal privilege should be that of the witness, and not that of the party, so that while the wife could decline to testify, she could not be prevented from giving evidence if she elected not to claim a privilege which, it was said, belonged to her alone. Brief for the United States, No. 20, O.T.1958, pp. 22 43. In declining to hold that the party had no privilege, we manifestly did not thereby repudiate the privilege of the witness.

While the question has not often arisen, it has apparently been generally assumed that the privilege resided in the witness as well as in the party. Hawkins referred to 'a rule which bars the testimony of one spouse against the other unless both consent,' supra, 358 U.S. at page 78, 79 S.Ct. at page 138. (Emphasis supplied.) See Stein v. Bowman, supra, 13 Pet. at page 223 (wife cannot 'by force of authority be compelled to state facts in evidence'); United States v. Mitchell, supra, 137 F.2d at page 1008 ('the better view is that the privilege is that of either spouse who chooses to claim it'); Wigmore, op. cit., supra, § 2241; McCormick, Evidence, § 66, n. 3. In its Hawkins brief, the Government, while calling for the abolition of the party's privilege, urged that the commonlaw development could be explained, and its policies fully vindicated, by recognition of the privilege of the witness. Brief, pp. 22—25, 33, 42—43; see Hawkins, supra, 358 U.S. at pages 77, and concurring opinion, at page 82, 79 S.Ct. at pages 139, 141. At least some of the bases of the party's privilege are in reason applicable to that of the witness. As Wigmore puts it, op. cit., supra, at p. 264: '(W)hile the defendant-husband is entitled to be protected against condemnation through the wife's testimony, the witness-wife is also entitled to be protected against becoming the instrument of that condemnation,—the sentiment in each case being equal in degree and yet different in quality.' In light of these considerations, we decline to accept the view that the privilege is that of the party alone.

Third. Neither can we hold that, whenever the privilege is unavailable to the party, it is ipso facto lost to the witness as well. It is a question in each case, or in each category of cases, whether, in light of the reason which has led to a refusal to recognize the party's privilege, the witness should be held compellable. Certainly, we would not be justified in laying down a general rule that both privileges stand or fall together. We turn instead to the particular situation at bar.

Where a man has prostituted his own wife, he has committed an offense against both her and the marital relation, and we have today affirmed the exception disabling him from excluding her testimony against him. It is suggested, however, that this exception has no application to the witness-wife when she chooses to remain silent. The exception to the party's privilege, it is said, rests on the necessity of preventing the defendant from sealing his wife's lips by his own unlawful act, see United States v. Mitchell, supra, 137 F.2d at pages 1008—1009; Wigmore, op cit., supra, § 2239, and it is argued that where the wife has chosen not to 'become the instrument' of her husband's downfall, it is her own privilege which is in question, and the reasons for according it to her in the first place are fully applicable.

We must view this position in light of the congressional judgment and policy embodied in the Mann Act. 'A primary purpose of the Mann Act was to protect women who were weak from men who were bad.' Denning v. United States, 5 Cir., 247 F. 463, 465. It was in response to shocking revelations of subjugation of women too weak to resist that Congress acted. See H.R.Rep. No. 47, 61st Cong., 2d Sess., pp. 10—11. As the legislative history discloses, the Act reflects the supposition that the women with whom it sought to deal often had no independent will of their own, and embodies, in effect, the view that they must be protected against themselves. Compare 18 U.S.C. § 2422, 18 U.S.C.A. § 2422 (consent of woman immaterial in prosecution under that section). It is not for us to re-examine the basis of that supposition.

Applying the legislative judgment underlying the Act, we are led to hold it not an allowable choice for a prostituted witness-wife 'voluntarily' to decide to protect her husband by declining to testify against him. For if a defendant can induce a woman, against her 'will,' to enter a life of prostitution for his benefit—and the Act rests on the view that he can—by the same token it should be considered that he can, at least as easily, persuade one who has already fallen victim to his influence that she must also protect him. To make matters turn upon ad hoc inquiries into the actual state of mind of particular women, thereby encumbering Mann Act trials with a collateral issue of the greatest subtlety, is hardly an acceptable solution.

Fourth. What we have already said likewise governs the disposition of the petitioner's reliance on the fact that his marriage took place after the commission of the offense. Again, we deal here only with a Mann Act prosecution, and intimate no view on the applicability of the privilege of either a party or a witness similarly circumstanced in other situations. The legislative assumption of lack of independent will applies as fully here. As the petitioner by his power over the witness could, as we have considered should be assumed, have secured her promise not to testify, so, it should be assumed, could he have induced her to go through a marriage ceremony with him, perhaps 'in contemplation of evading justice by reason of the very rule which is now sought to be invoked.' United States v. Williams, D.C., 55 F.Supp. 375, 380.

The ruling of the District Court was correctly upheld by the Court of Appeals.5

Affirmed.

Mr. Chief Justice WARREN, with whom Mr. Justice BLACK and Mr. Justice DOUGLAS join, dissenting.

Last Term this Court held that a wife could not voluntarily testify against her husband in a criminal prosecution over his objection. Hawkins v. United States, 358 U.S. 74, 79 S.Ct. 136, 3 L.Ed.2d 125. The Court finds the case at bar so different from Hawkins that it approves overriding not only the husband's objection, but also the wife's. In both cases the husband was prosecuted for violation of the Mann Act, 18 U.S.C. § 2421, 18 U.S.C.A. § 2421. The only relevant difference is that here the wife herself was the person allegedly transported by the husband for purposes of prostitution. Morally speaking, this profanation of the marriage relationship adds an element of the utmost depravity to the ugly business of promoting prostitution. Legally speaking, however, this does not warrant the radical departure from the Hawkins rule which the Court now sanctions.

The Court's analysis of the problem here presented is sound in so many ways that the unsoundness of its conclusion is especially disappointing—and somewhat curious. Briefly, that analysis appears to be as follows: The Court accepts the principle that the spousal privilege belongs both to the person charged with the offense, as we held in Hawkins, and also to the witness. Moreover, the Court rejects the notion that the latter may be barred from asserting the privilege simply because, in a given case, it may be improper for the former to invoke it. The defendant may not claim the privilege where he is charged with 'certain kinds of offenses committed * * * against his spouse,' and the Court believes that the instant case involves this type of crime. It apparently recognizes, moreover, that the policy behind this exception may be effectuated in the ordinary situation by giving the injured party the option to testify, without compelling her to testify.1 In this case, however, it concludes that the wife 'should be assumed' to be under the sway of the husband to such an extent that she cannot be entrusted with that choice. Consequently, the trial court—and the prosecutor—must be given the power to protect her against herself by forcing her to testify.

The fatal defect in this conclusion lies in the Court's evaluation of the mental state of the wife, an evaluation which finds no support in the record and which cannot properly be justified by any legislative enactment.

The Court does not and could not rely upon the record to prove that petitioner's wife was somehow mesmerized by him when she was on the witness stand. The evidence, in point of fact, strongly suggests that the wife played a managerial role in the sordid enterprise which formed the basis for the prosecution.2 Apparently this was the jury's view, since the jurors asked the judge whether it would 'make any difference or—if the woman had anything to do with the instigation or planning * * * .' The judge, of course, instructed then that this would be immaterial, but the jury nevertheless unanimously recommended leniency. Thus this case is a strange vehicle for the Court to use in announcing its 'lack of independent will' theory. Presumably it is to be regarded as the exception which proves the rule.

The sole ground assigned by the Court for its decision is that it is a necessary application of the 'legislative judgment underlying the (Mann) Act,' which 'reflects the supposition that the women with whom (Congress) sought to deal often had no independent will of their own, and embodies, in effect, the view that they must be protected against themselves.' In support of this hypothesis, the Court cites legislative history and the fact that, under 18 U.S.C. § 2422, 18 U.S.C.A. § 2422, a companion provision to § 2421, the consent of the woman does not relieve the defendant of criminal responsibility.3 This equation of the legislative judgment involved in fashioning a criminal statute with the judgment involved in the Court's restriction of the husband-wife privilege is, I submit, entirely too facile, for it overlooks the critically different nature of these problems. In assessing the pertinence of the woman's consent to the culprit's criminal responsibility, Congress chose between the interest of society in eradicating the importation and interstate transportation of prostitutes and the interest of women to be protected from clever and unscrupulous profiteers, on the one hand, and the voluntary engagement of women in prostitution on the other. In view of the manifest imbalance of these competing considerations and the difficulty of definition and proof of the type of consent which might conceivably be relevant, it is hardly surprising that Congress passed the Mann Act and made consent entirely immaterial under § 2422. The testimonial privilege, however, presents questions of quite a different order, since there is a significant interest traditionally regarded as supporting the privilege, as we recognized in Hawkins—the preservation of the conjugal relationship. And where the wife refuses to testify, there is strong evidence that there is still a marital relationship to be protected.

Not only does prior congressional action provide no support for the Court's decision, but without such support that decision represents an incursion into what is essentially a legislative area. It is true, of course, that federal courts have the authority to interpret the common-law principles of evidence 'in the light of reason and experience.' Fed.Rules Crim.Proc. rule 26, 18 U.S.C.A. This authority, however, must be exercised with a discriminating awareness of the distinction between matters which fall within the special competence of the judiciary and those which are primarily the concern of the legislature. It is more properly Congress' business, not ours, to place comparative values upon the quest for facts in the judicial process as against the safeguarding of the marriage relationship, and to give—or deny expression to what has been termed 'a natural repugnance in every fair-minded person to compelling a wife or husband to be the means of the other's condemnation, and to compelling the culprit to the humiliation of being condemned by the words of his intimate life-partner.' 8 Wigmore, Evidence, 227. That this decision is uniquely legislative and not judicial is demonstrated by the fact that, both in England and in this country, changes in the common-law privilege have been wrought primarily by legislatures.4 And perhaps it is worth noting that the essentials of the privilege have survived with remarkable sturdiness through the course of continued consideration by legislative bodies.5

Of particular interest is the past action and attitude of Congress with respect to the privilege. As the Court pointed out in Hawkins, in 1887 Congress passed a statute which permitted either spouse to testify in prosecutions of the other for the crimes of bigamy, polygamy, or unlawful cohabitation, but stipulated that neither should be compelled to testify. 24 Stat. 635. Apparently Congress believed that this provision gave sufficient protection to the spouse-witness, and that the interest of the State in securing convictions was outweighed by the considerations supporting the right of the spouse-witness not to testify against her will. Even more in point is the 1917 legislation by which Congress made spouses competent to testify against each other in prosecutions for the importation of aliens for immoral purposes. 39 Stat. 878—879, re-enacted as 66 Stat. 230, 8 U.S.C. § 1328, 8 U.S.C.A. § 1328. Thus Congress has acted with respect to the scope of the privilege in prosecutions under a statute kindred to § 2421, but has remained silent so far as § 2421 itself is concerned. The negative implication does not require elaboration.6 Moreover, it should be noted that even under § 1328 the testimony of the spouse is made only 'admissible and competent,' not compellable.7

In my judgment, the Court in this case strays from the course of appropriate judicial reserve marked by Hawkins. I am unwilling to join in a decision based upon an assumption of fact which is without support in the record and which involves a delicate, and essentially legislative determination. I therefore dissent.