Recognizing the effectiveness of physical barriers as a means of border control, Congress first mandated the construction of a border fence in 1996 as part of the Illegal Immigration Reform and Immigrant Responsibility Act (IIRIRA). IIRIRA called for the construction of a 14-mile, triple-layered fence along the boundary between San Diego and Tijuana.
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By 2004, only nine miles of fencing were completed. Congress subsequently passed the Secure Fence Act of 2006. That legislation called for double-layered fencing along the border, augmented by manpower and technology, and directed the Secretary of Homeland security to construct “reinforced fencing along not fewer than 700 miles of the southwest border, in locations where fencing is deemed most practical and effective.”
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