or shall conceal or harbor, or attempt to conceal or harbor, or assist or abet another to conceal or harbor in any place . . . any alien not duly admitted by an immigrant inspector or not lawfully entitled to enter or to reside within the United States under the terms of this Act, shall be deemed guilty of a misdemeanor, and upon conviction thereof shall be punished by a fine not exceeding $2,000 and by imprisonment for a term not exceeding five years, for each and every alien so landed or brought in or attempted to be landed or brought in." (Emphasis added.) 39 Stat. 880, 8 U. S. C. § 144. Appellee and another were indicted for concealing and harboring five named aliens in alleged violation of § 8. Before trial appellee moved that the indictment be dismissed on the ground that it did not charge a punishable offense. He argued that although the statute provided for two different crimes, one landing or bringing in unauthorized aliens, and the other concealing or harboring such aliens, punishment was prescribed in terms only for the former crime. The District Court accepted this argument and granted the motion to dismiss. The Government appealed directly to this Court pursuant to the Criminal Appeals Act, 28 U. S. C. § 345, and we noted probable jurisdiction. The case presents an unusual and a difficult problem in statutory construction. It concerns not so much Congress' intention to make concealing or harboring criminal as it does the penalty to be applied to those offenses including attempts. The choice, as might appear on glancing at the statute, is not simply between no penalty, at the one extreme, and, at the other, fine plus imprisonment up to the specified maxima for each alien concealed or harbored. The problem is rather one of multiple choice, presenting at least three, and perhaps four, possible yet 483 Opinion of the Court. inconsistent answers on the statute's wording. Furthermore, as will appear, the legislative history is neither clear nor greatly helpful in ascertaining which of the possibilities calling for punishment was the one Congress contemplated. Before discussing specifically the alternatives, we note that the Government rests primarily on the clarity with which § 8 indicates Congress' purpose to make concealing or harboring criminal, rather than upon any like indication of legislative intent concerning the penalty.1 Because the purpose to proscribe the conduct is clear, it is said, we should not allow that purpose to fail because of ambiguity concerning the penalty. Rather we are asked to make it effective by applying that one of the possibilities which seems most nearly to accord with the criminal proscription and the terms of the penalizing provision. 2 On the other hand, appellee does not really dispute that Congress meant, by inserting the amendment prohibiting concealing or harboring, to make those acts criminal. But he denies that it is possible, either from the section's wording or from the legislative history, to ascertain with any fair degree of assurance which one of the possible penal consequences Congress may have had in mind. From this he falls back upon the conclusion indicated by the premise, namely, that the task of resolving the difficulty goes beyond dispelling ambiguity in the usual sense 1 Since the issues arise on dismissal of the indictment which charges both concealing and harboring, as well as attempt to conceal and harbor, we are not asked to determine whether "conceal or harbor" as used in § 8 specifies only one offense or two distinct ones or, if the latter, the difference between the two. Cf. notes 7 and 8 infra and text. 2 Section 8 as enacted originally in 1907, 34 Stat. 900, covered only bringing in or landing and attempts to bring in or land. The prohibition of concealing or harboring and of attempting to conceal or harbor was added by amendment in 1917. 39 Stat. 880. 776154 0-48-36 Opinion of the Court. 333 U.S. of judicially construing statutes 3 and, if attempted, would require this Court to invade the legislative function and, in effect, fix the penalty. The argument is therefore not merely that a rule of strict construction should be applied in petitioner's favor. It is rather that the choice the Government asks us to make is so broad and so deep, resting among such equally tenable though inconsistent possibilities, that we have no business to make it at all. Even in criminal matters a strong case would be required to bring about the result appellee seeks. For, where Congress has exhibited clearly the purpose to proscribe conduct within its power to make criminal and has not altogether omitted provision for penalty, every reasonable presumption attaches to the proscription to require the courts to make it effective in accord with the evident purpose. This is as true of penalty provisions as it is of others. United States v. Brown, 333 U. S. 18. But strong as the presumption of validity may be, there are limits beyond which we cannot go in finding what Congress has not put into so many words or in making certain what it has left undefined or too vague for reasonable assurance of its meaning. In our system, so far at least as concerns the federal powers, defining crimes and fixing penalties are legislative, not judicial, functions.* But given some legislative edict, the margin between the necessary and proper judicial function of construing stat 3 Indeed appellee asserts that the words of § 8 are unambiguously to the effect that fine and imprisonment are to be imposed "for each and every alien so landed or brought in . . .," not "for each and every alien so concealed or harbored." This view regards the concluding "for each and every alien" clause as an integral and inseparable part of the penalty provision for all offenses punishable under the section. 4 United States v. Hudson and Goodwin, 7 Cranch 32; United States v. Britton, 108 U. S. 199; United States v. Eaton, 144 U. S. 677; Viereck v. United States, 318 U. S. 236, 241, 243–244. 483 Opinion of the Court. utes and that of filling gaps so large that doing so becomes essentially legislative, is necessarily one of degree. We turn then to consider whether the Government is asking that we do too much when it puts forward a preferred reading of the penal provision, perhaps suggests another as a permissible alternative, and is prepared to accept a third, though disavowing its complete consistency with Congress' intent, if neither of the others is adopted. The Government's preferred reading would impose the same penalty for concealing or harboring as for bringing in or landing, notwithstanding the "for each and every alien" clause is limited expressly to aliens "so landed or brought in or attempted to be landed or brought in." Under this interpretation the effect of that clause would be to provide additional punishment, as stated in the brief, "where the crime of landing or bringing in aliens or the crime of concealing or harboring aliens involves more than one alien brought into the country illegally." (Emphasis added.) This construction is admittedly ungrammatical and the failure to integrate the wording of the "each and every alien" clause with the language of the 1917 amendment adding the concealing and harboring offenses is conceded to have been possibly due to oversight. If only imperfect grammar stood in the way, the construction might be accepted. But we agree with appellee that more is involved. The Government in effect concedes that in terms the section prescribes no penalty for concealing or harboring. But it argues that inclusion of them as offenses becomes meaningless unless the penalty provision, in spite of its wording, is construed to apply to them as well as to bringing in or landing. In other words, because Congress intended to authorize punishment, but failed to do so, probably as a result of oversight, we should plug the hole in the statute. Opinion of the Court. 333 U.S. To do this would be to go very far indeed, upon the sheer wording of the section. For it would mean in effect that we would add to the concluding clause the words which the Government's reading inserts, "and for each and every alien so concealed or harbored." It is possible that Congress may have intended this. But for more than one reason we cannot be sure of that fact. In the first place, the section as originally enacted was limited to acts of smuggling. And there is some evidence in the legislative history that the addition of concealing or harboring was meant to be limited to those acts only when closely connected with bringing in or landing, so as to make a chain of offenses consisting of successive stages in the smuggling process." But that evidence is not conclusive." And the section's wording is susceptible of much broader constructions. On the language it is possible not only to treat concealing or harboring as offenses distinct and disconnected from smuggling operations; it is also possible to regard them as separate and distinct from each other. And on the broadest possible interpretation, giving independent effect to the words "or not lawfully entitled . . . to reside within the United States," the section could be taken 5 The Senate Report accompanying the 1917 amendment stated that "such new provisions as are included are merely to complete the definition of the crime of smuggling aliens into the United States and related offenses . . . ." Sen. Rep. No. 352, 64th Cong., 1st Sess. 9. There is no indication of the degree or character of the relation suggested by the words "and related offenses," see the preceding note, with reference to the proximity of the acts proscribed, in time and place, to smuggling operations. 7 This possibility apparently is not comprehended by the indictment in this case, which substitutes "and" for the "or" given by the statutory wording in describing the aliens charged to have been concealed and harbored, viz., "which said alien persons then and there were aliens not duly admitted to the United States by an |