delivered the opinion of the Court.
The question for decision is whether § 2 of the National Firearms Act of June 26, 1934, c. 757, 48 Stat. 1236, 26 U. S. C., §§ 1132-1132 q, which imposes a 1200 annual license tax on dealers in firearms, is a constitutional exercise of the legislative power of Congress.
Petitioner was convicted by the District Court for Eastern Illinois on two counts of an indictment, the first charging him with violation of § 2, by dealing in firearms without payment of the tax. On appeal the Court of Appeals set aside the conviction on the second count and affirmed on the first. 86 F. (2d) 486. On petition of the accused we granted certiorari, limited to the question of the constitutional validity of the statute in its application under the first count in the indictment.
Section 2 of the National Firearms Act requires every dealer in firearms to register with the Collector of Internal Revenue in the district where he carries on business, and to pay a special excise tax of $200 a year. Importers or manufacturers are taxed $500 a year. Section 3 imposes a. tax of $200 on each transfer of a firearm, payable by the transferor, and § 4 prescribes regulations for the identification of purchasers. The term “firearm” is defined by § 1 as meaning a shotgun or a rifle having a barrel less than eighteen inches in length, or any other weapon, ex
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cept a pistol or revolver, from which a shot is discharged by an explosive, if capable of being concealed on the person, or a machine gun, and includes a muffler or silencer for any firearm. As the conviction for, nonpayment of the tax exacted by § 2 has alone been sustained, it is unnecessary to inquire whether the different tax levied by § 3 and the regulations pertaining to it are valid. Section 16 declares that the provisions of the Act are separable. Each tax is on a different activity and is collectible independently of the other. Full effect may be given to the license tax standing alone, even though all other provisions are invalid.
Weller
v.
New York,
In the exercise of its constitutional power to lay taxes, Congress may select the subjects of taxation, choosing some and omitting others. See
Flint
v.
Stone Tracy Co.,
The case is not one where the statute contains regulatory provisions related to a purported tax in such a way as has enabled this Court to say in other cases that the latter is a penalty resorted to as a means of enforcing the regulations. See
Child Labor Tax Case,
Every tax is in some measure regulatory. To some extent it interposes an economic impediment to the activity taxed as compared with others not taxed. But a tax is not any the less a tax because it has a regulatory effect,
United States
v.
Doremus, supra,
93, 94;
Nigro
v.
United States,
Inquiry into the hidden motives which may move Congress to exercise a power constitutionally conferred upon
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it is beyond the competency of courts.
Veazie Bank
v.
Fenno, supra; McCray
v.
United States, supra,
56-59;
United States
v.
Doremus, supra,
93-94; see
Magnano Co.
v.
Hamilton,
• Here the annual tax of $200 is productive of some revenue.
1
We are not free to speculate as to the motives which moved Congress to impose it, or as to the extent to which it may operate to restrict the activities taxed. As it is not attended by an offensive regulation, and since it operates as a tax, it is within the national taxing power.
Alston
v.
United States,
We do not discuss petitioner’s contentions which he failed to assign as error below.
Affirmed.
Notes
The $200 tax was paid by 27 dealers in 1934, and by 22 dealers in 1935. Annual Report of the Commissioner of Internal Revenue, Fiscal Year Ended Tune 30, 1935, pp. 129-131; id., Fiscal Year ended June 30, 1936, pp. 139-141.
