The Sixteenth Amendment to the United States Constitution, ratified in 1913, grants Congress the power to levy taxes on incomes from any source without apportioning the tax among the states based on population. This amendment overturned the Supreme Court's 1895 Pollock decision, which had restricted federal income tax as a direct tax requiring apportionment. The change it created was a fundamental shift that allowed the federal government to impose a nationwide income tax freely, leading to the establishment of the modern progressive income tax system. This amendment transformed federal revenue sources from primarily tariffs and excise taxes to income taxes, significantly increasing the government's fiscal power for funding public needs and redistributing tax burdens more equitably among citizens.
