In addition to passing sweeping legislation regulating business, promoting moral improvement, expanding democracy, and advancing scientific principles, the Progressive reformers also added four amendments to the United States Constitution that made fundamental changes in the way that the federal government interacted with the states and the people. The Sixteenth Amendment authorized the federal government to collect an income tax, while the Seventeenth Amendment mandated the direct election of senators. The Eighteenth Amendment began a failed experiment with Prohibition, while that Nineteenth Amendment began a long and lasting process of bringing women into American politics by recognizing the right of women to vote.