The Second Amendment (Amendment II) to the United States Constitution is the part of the United States Bill of Rights that protects the right to keep and bear arms. It was adopted on December 15, 1791, along with the rest of the Bill of Rights.
The right to bear arms predates the Bill of Rights; the Second Amendment was based partially on the right to bear arms in English common-law, and was influenced by the English Bill of Rights of 1689. This right was described by Blackstone 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. Academic inquiry into the purpose, scope, and effect of the amendment has been controversial and subject to numerous interpretations.
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