dissenting.
Had the majority in judging this case been content to confine itself to applying relevant rules of law and to leave policies affecting the proper conservation of the Nation’s rivers to be dealt with by the Congress, I think that today’s decision in this criminal case would have eventuated differently. The best that can be said for the Government’s case is that the reach of the provision of *231§ 13 of the Rivers and Harbors Act of 1899, 30 Stat. 1152, 33 U. S. C. § 407 (1964 ed.), under which this indictment is laid, is uncertain. This calls into play the traditional rule that penal statutes are to be strictly construed. In my opinion application of that rule requires a dismissal of the indictment.
I.
Section 13 forbids the deposit of all kinds of “refuse matter” into navigable rivers “other than that flowing from streets and sewers and passing therefrom in a liquid state.” As the Court notes, this 1899 Act was part of a codification of prior statutes. This revamping was not discussed at any length on the floor of either House of Congress; the Senate was informed only that the provisions were merely a codification of existing law, without changes in substance. 32 Cong. Rec. 2296-2297 (1899). Section 13 was in fact based on two very similar prior statutes. The rivers and harbors appropriation act of 1890 provided the first national anti-obstruction provision, 26 Stat. 453:
“Sec. 6. That it shall not be lawful to cast, throw, empty, or unlade, or cause, suffer, or procure to be cast, thrown, emptied, or unladen, either from or out of any ship, vessel, lighter, barge, boat, or other craft, or from the shore, pier, wharf, furnace, manufacturing establishments, or mills of any kind whatever, any ballast, stone, slate, gravel, earth, rubbish, wreck, filth, slabs, edgings, sawdust, slag, cinders, ashes, refuse, or other waste of any kind, into any port, road, roadstead, harbor, haven, navigable river, or navigable waters of the United States which shall tend to impede or obstruct navigation . . . .”
A later statute, § 6 of the Rivers and Harbors Act of 1894, 28 Stat. 363, provided somewhat similarly:
“That it shall not be lawful to place, discharge, or deposit, by any process or in any manner, ballast, *232refuse, dirt, ashes, cinders, mud, sand, dredgings, sludge, acid, or any other matter of any kind other than that flowing from streets, sewers, and passing therefrom in a liquid state, in the waters of any harbor or river of the United States, for the improvement of which money has been appropriated by Congress . . . .”
The Court relies primarily on the latter Act, contending that its applicability to “any other matter of any kind” would surely encompass oil, even though commercially valuable. Further, the Court notes (ante, p. 228) that the 1894 statute was modeled after a federal statute of 1888 dealing with New York Harbor, 25 Stat. 209. Under this New York Harbor Act, which still remains on the books, 33 U. S. C. § 441 et seq. £1964 ed.), prosecutions for accidental deposits of commercially useful oil have been sustained. The Colombo, 42 F. 2d 211. This background is thought to reinforce the view that oil of any type would fall within the 1894 statute’s purview. Since the present enactment was intended to be merely a codification, the majority concludes that the construction of the broader 1894 predecessor should govern.
Whatever might be said about how properly to interpret the 1890 and, more especially, the 1894 statutes, it is the 1899 Act that has been on thé books for the last 67 years, and its purposes and language must guide the determination of this case. To the extent that there were some differences in scope between the 1890 and 1894 Acts, these were necessarily resolved in the 1899 codification, which, while embodying the essential thrust of both prior statutes, appears from its plain language to have favored the more restrictive coverage of the 1890 Act. Moreover, it is questionable to what extent the Court’s speculation as to the meaning of a phrase in one of the prior statutes is relevant at all when the language of the pres*233ent statute, which is penal in nature, is in itself explicit and unambiguous.
The purpose of § 13 was essentially to eliminate obstructions to navigation and interference with- public works projects. This 1899 enactment, like the two preexisting statutes which it was intended to codify, was a minor section attached to a major appropriation act together with other measures dealing with sunken wrecks,1 trespassing at public works sites,2 and obstructions caused by improperly constructed bridges, piers, and other structures.3 These statutes were rendered necessary primarily because navigable rivers, which the Congress was appropriating funds to improve, were being obstructed by depositing of waste materials by factories and ships.4 It is of course true, as the Court observes, that “oil is oil,” ante, p. 226, and that the accidental spillage of valuable oil may have substantially the same “deleterious effect on waterways” as the wholesale depositing of waste oil. But the relevant inquiry is not the admittedly important concerns of pollution control, but Congress’ purpose in enacting this anti-obstruction Act, and that appears *234quite plainly to be a desire to halt through the imposition of criminal penalties the depositing of obstructing refuse matter in rivers and harbors.
The Court’s construction eschews the everyday meaning of “refuse matter” — waste, rubbish, trash, debris, garbage, see Webster’s New International Dictionary, 3d ed. — and adopts instead an approach that either reads “refuse” out of the Act altogether, or gives to it a tortured meaning. The Court declares, at one point, that “The word ‘refuse’ includes all foreign substances and pollutants apart from those ‘flowing from streets and sewers and passing therefrom in a liquid state’ into the watercourse.” Ante, p. 230. Thus, dropping anything but pure water into a river would appear to be a federal misdemeanor. At the same time, the Court also appears to endorse the Second Circuit’s somewhat narrower view that “refuse matter” refers to any material, however valuable, which becomes unsalvageable when introduced into the water. Ante, pp. 229-230. On this latter approach, the imposition of criminal penalties would in effect depend in each instance on a prospective estimate of salvage costs. Such strained definitions of a phrase that is clear as a matter of ordinary English hardly commend themselves, and at the very least raise serious doubts as to the intended reach of § 13.
II.
Given these doubts as to the proper construction of “refuse matter” in § 13, we must reckon with a traditional canon that a penal statute will be narrowly construed. See II Hale, Historia Placitorum Coronae 335 (1736); United States v. Wiltberger, 5 Wheat. 76, 95. The reasons underlying this maxim are various. It appears likely that the rule was originally adopted in order to spare people from the effects of exceedingly harsh penalties. See Hall, Strict or Liberal Construction of Penal *235Statutes, 48 Harv. L. Rev. 748, 750 (1935). Even though this rationale might be thought to have force were the defendant a natural person,5 I cannot say that it is particularly compelling in this instance where the maximum penalty to which Standard Oil might be subject is a fine of $2,500. 33 U. S. C. § 411 (1964 ed.).
A more important contemporary purpose of the notion of strict construction is to give notice of what the law is, in order to guide people in their everyday activities. Again, however, it is difficult to justify a narrow reading of § 13 on this basis. The spilling of oil of any type into rivers is not something one would be likely to do whether or not it is legally proscribed by a federal statute. A broad construction would hardly raise dangers of penalizing people who have been innocently pouring valuable oil into navigable waters, for such conduct in Florida is unlawful whatever the effect of § 13. A Florida statute penalizing as a misdemeanor the depositing into waters within the State of “any rubbish, filth, or poisonous or deleterious substance or substances, liable to affect the health of persons, fish, or live stock . . . ,” Fla. Stat. Ann., §387.08 (1960 ed.), quite evidently reaches the dumping of commercial oil. And Florida’s nuisance law would likewise seem to make this conduct actionable in equity. See, e. g., The Ferry Pass Inspectors’ & Shippers’ Assn. v. The Whites River Inspectors’ & Shippers’ Assn., 57 Fla. 399, 48 So. 643. Finally, as noted earlier, ante, p. 229, n. 5, prior decisions by some lower courts have held § 13 applicable to spillage of oil. For these reasons this justification for the canon of strict construction is not persuasive in this instance.
*236There is, however, a further reason for applying a seemingly straightforward statute in a straightforward way. In McBoyle v. United States, 283 U. S. 25, this Court held that a statute making it a federal crime to move a stolen “motor vehicle” in interstate commerce did not apply to a stolen airplane. That too was a case in which precise clarity was not required in order to give due warning of the line between permissible and wrongful conduct, for there could not have been any question but that stealing aircraft was unlawful. Nevertheless, Mr. Justice Holmes declared that “Although it is not likely that a criminal will carefully consider the text of the law before he murders or steals, it is reasonable that a fair warning should be given to the world in language that the common world will understand, of what the law intends to do if a certain line is passed.” 283 U. S., at 27. The policy thus expressed is based primarily on a notion of fair play: in a civilized state the least that can be expected of government is that it express its rules in language all can reasonably be expected to understand. Moreover, this requirement of clear expression is essential in a practical sense to confine the discretion of prosecuting authorities, particularly important under a statute such as § 13 which imposes criminal penalties with a minimal, if any, scienter requirement.6
In an area in which state or local law has traditionally regulated primary activity,7 there is good reason to re*237strict federal penal legislation within the confines of its language. If the Federal Government finds that there is sufficient obstruction or pollution of navigable waters caused by the introduction of commercial oil or other nonrefuse material, it is an easy matter to enact appropriate regulatory or penal legislation.8 Such legislation can be directed at specific types of pollution, and the remedies devised carefully to ensure compliance. Indeed, such a statute was enacted in 1924 to deal with oil pollution in coastal waters caused by vessels, 43 Stat. 605, 33 U. S. C. §§ 433, 434 (1964 ed.).
To conclude that this attempted prosecution cannot stand is not to be oblivious to the importance of preserving the beauties and utility of the country’s rivers. It is simply to take the statute as we find it. I would affirm the judgment of the District Court.
Rivers and Harbors Act of 1899, § 15, 30 Stat. 1152, 33 U. S. C. § 409 (1964 ed.).
Rivers and Harbors Act of 1899, § 14, 30 Stat. 1152, 33 U. S. C. §408 (1964 ed.).
Rivers and Harbors Act of 1899, § 12, 30 Stat. 1151, 33 U. S. C. §406 (1964 ed.).
Congress was presented, when considering one of the predecessors of the 1899 Act, with the representations of the Office of the Chief of Army Engineers that there had been “serious injury to navigable waters by the discharge of sawmill waste into streams .... In fair-ways of harbors, channels are injured from deposits of ballast, steam-boat ashes, oysters, and rubbish from passing vessels.” S. Rep. No. 224, 50th Cong., 1st Sess., 2 (1888). See also H. R. Rep. No. 1826, 55th Cong., 3d Sess., 3-4 (1899). There is no support for the proposition that these statutes were directed at “pollution” independently of “obstruction.”
The minimum sentence for an individual convicted of violating § 13 is a $500 fine or 30 days’ imprisonment, not an insignificant penalty for accidentally dropping foreign matter into a river. 33 U. S. C. §411 (1964 ed.).
The parties were not in agreement as to what scienter requirement the statute imposes. This question is not before us under the restricted jurisdiction granted to this Court under 18 U. S. C. § 3731 (1964 ed.), see United States v. Petrillo, 332 U. S. 1; United States v. Borden Co., 308 U. S. 188, and the Court today intimates no views on the question.
Besides the Florida pollution statute adverted to earlier, Fla. Stat. Ann., §387.08 (1960 ed.), the*city of Jacksonville has enacted ordinances dealing generally with fire prevention, Jacksonville Ordi*237nance Code §§19-4.1 to 19-4.24 (1958 Supp.), disposal of waste material, §21-12 (1958 Supp.), and pollution of the city water supply, §27-52 (1953 Code).
See, e. g., special message of the President dealing with new antipollution legislation, Preservation of Our Natural Heritage — Message from the President of the United States, H. Doc. No. 387, 89th Cong., 2d Sess., Cong. Rec., Feb. 23, 1966, pp. 3519-3522.