From Somewhat Reasonable:

Each version of the bill has also attracted a wide array of critics, who argued in a letter to Congress that the Act would override important tax precedents and harm consumers. The letter was co-signed by several conservative, free market and libertarian groups, including The Heartland Institute, R Street Institute, Americans for Tax Reform, Americans for Prosperity and FreedomWorks. In the letter, the group argued the Marketplace Fairness Act would “dismantle proper limits on state tax collection authority while causing serious damage to electronic and interstate commerce.”

…Critics argue the bill has not improved over time. “This was a bad bill in the last Congress and it’s still a bad bill now,” said Andrew Moylan, R Street executive director in a statement. “By wiping away geographic limits to state tax authority, the legislation would impose serious burdens on Internet retail and undermine basic tax policy principles.”

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