The Immigration and Nationality Act, sometimes known as the INA, is the basic body of immigration law in the United States. It was created in 1952. A variety of statutes governed immigration law before this, but they weren't organized in one location. The INA is also known as the McCarran-Walter Act, named after the bill's sponsors: Senator Pat McCarran (D-Nevada), and Congressman Francis Walter (D-Pennsylvania).
The INA deals with "Aliens and Nationality." It's divided into titles, chapters, and sections. Although it stands alone as a single body of law, the Act is also contained in the United States Code (U.S.C.).
You'll often see references to the U.S. Code citation when you're browsing the INA or other statutes. For example, Section 208 of the INA deals with asylum, and it is also contained in 8 U.S.C. 1158. It's technically correct to refer to a specific section by either its INA citation or its U.S. code, but the INA citation is more commonly used.
The Act kept many of the same immigration policies from earlier statutes with some major changes. Racial restrictions and gender discrimination were eliminated. The policy of restricting immigrants from certain countries remained, but the quota formula was revised. Selective immigration was introduced by giving a quota preference to aliens with much-needed skills and relatives of U.S. citizens and alien residents. The Act introduced a reporting system whereby all U.S. aliens were required to report their current address to the INS each year, and it established a central index of aliens in the U.S. for use by security and enforcement agencies.
President Truman was concerned about the decisions to maintain the national origins quota system and to establish racially constructed quotas for Asian nations. He vetoed the McCarran-Walter Act because he regarded the bill as discriminatory. Truman's veto was overridden by a vote of 278 to 113 in the House and 57 to 26 in the Senate.
The original 1952 Act has been amended many times over the years. The biggest change occurred with the Immigration and Nationality Act Amendments of 1965. That bill was proposed by Emanuel Celler, cosponsored by Philip Hart, and heavily supported by Senator Ted Kennedy.
The 1965 amendments abolished the national origins quota system, eliminating national origin, race or ancestry as a basis for immigration to the U.S. They established a preference system for relatives of U.S. citizens and permanent residents, and for persons with special occupational skills, abilities or training. They also established two categories of immigrants who would not be subject to numerical restrictions: immediate relatives of U.S. citizens and special immigrants.
The amendments did maintain the quota restriction. They expanded limits to world coverage by limiting Eastern Hemisphere immigration and by placing a ceiling on Western Hemisphere immigration for the first time. Neither the preference categories nor the 20,000 per-country limit was applied to the Western Hemisphere, however.
The 1965 legislation introduced a prerequisite for the issuance of a visa that an alien worker will not replace a worker in the U.S. nor adversely affect the wages and working conditions of similarly employed individuals.
The House of Representatives voted 326 to 69 in favor of the act, while the Senate passed the bill by a vote of 76 to 18. President Lyndon B. Johnson signed the legislation into law on July 1, 1968.
Some immigration reform bills that would amend the current INA have been introduced into Congress in recent years. They include the Kennedy-McCain Immigration Bill of 2005 and the Comprehensive Immigration Reform Act of 2007. This was introduced by Senate Majority Leader Harry Reid and co-authored by a bipartisan group of 12 senators including Senator Ted Kennedy and Senator John McCain.
None of these bills made it through Congress, but the 1996 Illegal Immigration Reform and Immigrant Responsibility Act toughened up border control and clamped down on welfare benefits for legal aliens. The REAL ID Act of 2005 was then passed, requiring proof of immigration status or citizenship before states can issue certain licenses. No less than 134 bills regarding immigration, border security, and related issues were introduced in Congress as of mid-May 2017.
The most current version of the INA can be found on the USCIS website under "Immigration and Nationality Act" in the Laws and Regulations section.