312 U.S. 52 (1941)
In 1939 the Commonwealth of Pennsylvania adopted an Alien Registration Act requiring every alien eighteen years of age or older, with limited exceptions, to register annually with the Department of Labor and Industry, supply specified information plus any additional details the department might direct, pay a one-dollar annual fee, receive an identification card, carry the card at all times, and exhibit it on demand by any police officer or department agent.1 One alien and one naturalized citizen filed suit in federal district court against state officials charged with enforcing the statute and sought an injunction against its operation.2 A three-judge district court granted judgment on the pleadings in favor of the alien plaintiff and enjoined enforcement of the Act.3
The case reached the Supreme Court on direct appeal under section 266 of the Judicial Code, with probable jurisdiction noted on March 25, 1940.4 After the district court decision but before Supreme Court review, Congress on June 28, 1940 enacted a federal Alien Registration Act that requires a single registration of aliens fourteen years of age and older, collects detailed information plus additional matters prescribed by the Commissioner with the Attorney General's approval, mandates fingerprinting of all registrants, and directs that registration records be kept secret and released only to persons or agencies designated by the Commissioner with the Attorney General's approval.5 The federal statute contains no requirement that aliens carry identification cards for exhibition to police or other officials and punishes only willful failure to register.6
The Supreme Court therefore examined the Pennsylvania statute in light of the intervening federal legislation.7
Whether Congress by enacting the Alien Registration Act of 1940 has precluded enforcement of Pennsylvania's 1939 Alien Registration Act?8
When the federal government has enacted a complete scheme of regulation for the registration of aliens, states cannot enforce additional or auxiliary regulations that conflict or interfere with the federal law.9 States also cannot enforce regulations that stand as an obstacle to the accomplishment and execution of the full purposes and objectives of Congress.10
Yes. The case arose when Pennsylvania enacted its Alien Registration Act in 1939.11 The statute required every alien eighteen years of age or older, with limited exceptions, to register annually with the Department of Labor and Industry, supply specified information plus any additional details the department might direct, pay a one-dollar annual fee, receive an identification card, carry the card at all times, and exhibit it on demand by any police officer or department agent. One alien and one naturalized citizen filed suit in federal district court against state officials charged with enforcing the statute and sought an injunction against its operation.
A three-judge district court granted judgment on the pleadings in favor of the alien plaintiff and enjoined enforcement of the Act. The case reached the Supreme Court on direct appeal under section 266 of the Judicial Code, with probable jurisdiction noted on March 25, 1940. After the district court decision but before Supreme Court review, Congress on June 28, 1940 enacted a federal Alien Registration Act that requires a single registration of aliens fourteen years of age and older, collects detailed information plus additional matters prescribed by the Commissioner with the Attorney General's approval, mandates fingerprinting of all registrants, and directs that registration records be kept secret and released only to persons or agencies designated by the Commissioner with the Attorney General's approval. The federal statute contains no requirement that aliens carry identification cards for exhibition to police or other officials and punishes only willful failure to register.
The federal Alien Registration Act of 1940 establishes a single registration requirement with fingerprinting and secrecy provisions.12 In contrast, the Pennsylvania Alien Registration Act of 1939 requires annual registration, payment of a fee, carrying of an identification card at all times, and exhibition upon demand by police officers.13 These additional requirements of the state law conflict with the uniform national system designed to protect the personal liberties of law-abiding aliens and to avoid inquisitorial practices.14 Therefore, the Pennsylvania statute stands as an obstacle to the full purposes of Congress and cannot be enforced.15
The judgment of the district court is affirmed because Congress has precluded enforcement of the state act through its comprehensive federal registration scheme.16
Related opinions on this issue
Joined by The Chief Justice And Mr. Justice Mcreynolds
Justice Stone dissented on the ground that the federal act does not preclude the state law.17 He argued that there is no direct conflict between the two statutes.18 Congress did not express an intent to occupy the field exclusively.19
Congress also did not intend to withdraw from the states any part of their constitutional power over aliens within their borders.20 In his view, the state statute was a valid exercise of the police power.21 That power can stand consistently with the federal registration requirements.22
The enforcement of both acts involves no more inconsistency than other dual sovereignty laws such as revenue laws.23