The Twenty-fourth Amendment prohibits the use of poll taxes in federal elections, either in primaries or general elections. Such taxes, also known as head taxes, were often used in a discriminatory manner to prevent access to the ballot, especially for poor whites and racial minorities. Although only a few states still used the poll tax in the early 1960s, Congress thought the problem was best solved by a constitutional amendment, since states traditionally controlled elections. The amendment was passed by Congress in 1962 and ratified in 1964.