What amendment prohibited poll taxes?

The 24th Amendment to the United States Constitution, ratified in 1964, prohibited the use of poll taxes in federal elections. It was designed to eliminate financial barriers that disproportionately affected low-income individuals and minorities, ensuring that voting rights were not contingent on the ability to pay a tax. In 1966, the Supreme Court further extended this prohibition to state elections in the case of Harper v. Virginia Board of Elections.