Before the creation of the Immigration and Nationality Act (INA) in 1952, United States immigration law was governed by a variety of different statutes. The passage of the act consolidated these statutes into the basic body of immigration law. This is separated into sections, chapters, and titles under the United States Code, the compilation of federal U.S. laws.
Also known as the McCarran-Walter Act, the law was named after its sponsors, Congressman Francis Walter and Senator Pat McCarran. Although several immigration policies from the earlier statutes were kept in the new law with few changes, gender discrimination and racial restrictions were eventually removed. A self-reporting system was introduced, under which foreign citizens must report their address each year to the federal Immigration and Naturalization Service. For use by law enforcement and security agencies, a central index of aliens living in the United States was established.
Over the years, the 1952 law was amended several times. The biggest changes were introduced with the passage of the Immigration and Nationality Act Amendments of 1965, when national origin, ancestry, and race as the basis for immigration were removed from the law. In addition, a preference system was established which favours potential immigrants who have special abilities or much-needed skills, and also foreign nationals who are the relatives of US citizens.
Work to improve the present Immigration and Nationality Act continues, with several immigration reform bills having been submitted to Congress. However, none of these bills has so far passed into law.