House Speaker Mike Madigan is responding to mounting pressure on House Democrats to oppose a progressive tax by filing a resolution of his own.

Madigan introduced House Resolution 1025 on April 26, and 42 Democratic lawmakers have signed on so far. Meanwhile, 50 House Republicans have signed on to a resolution opposing a progressive tax.

While Madigan would have Illinoisans believe it would only be a tax increase on the rich, recent history and Illinois’ spending problems dictate the middle class would face tax hikes under a progressive tax system – where income is taxed at increasingly higher rates, rather than the current flat rate of 4.95 percent.

Proponents of scrapping Illinois’ constitutionally protected flat tax make three key claims: a progressive tax would cut taxes on the middle class, it would go a long way toward reducing income inequality and it would benefit the state’s economy.

These claims are misleading at best.

States with progressive income taxes have seen slower economic growth and faster growth in inequality. Most economists agree that more progressive tax structures reduce economic growth. And one of the rare progressive tax proposals to outline an actual tax structure in Illinois would hike income taxes on residents earning as little as $17,300, inflicting serious damage on an already-weak state economy.

Given proposals like this, it’s no wonder nearly 25,000 Illinois taxpayers have signed on to a petition opposing a progressive income tax via illinoispolicy.org. A poll conducted by Illinois Policy found 42 percent of active likely voters in Illinois oppose a progressive tax, with 29 percent unsure or having no opinion, and 29 percent supporting.