Second Amendment to the U.S. Constitution

The Second Amendment (Amendment II) to the United States Constitution protects the right of the people to keep and bear arms and was adopted on December 15, 1791, as part of the first ten amendments contained in the Bill of Rights. The Supreme Court of the United States has ruled that the right belongs to individuals, while also ruling that the right is not unlimited and does not prohibit all regulation of either firearms or similar devices.State and local governments are limited to the same extent as the federal government from infringing this right per the incorporation of the Bill of Rights.

The Second Amendment was based partially on the right to keep and bear arms in English common law and was influenced by the English Bill of Rights of 1689. Sir William Blackstone described this right as an auxiliary right, supporting the natural rights of self-defense, resistance to oppression, and the civic duty to act in concert in defense of the state.

In United States v. Cruikshank (1876), the Supreme Court of the United States ruled that, "The right to bear arms is not granted by the Constitution; neither is it in any manner dependent upon that instrument for its existence" and limited the applicability of the Second Amendment to the federal government. In United States v. Miller (1939), the Supreme Court ruled that the federal government and the states could limit any weapon types not having a "reasonable relationship to the preservation or efficiency of a well regulated militia."

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