Democratic presidential candidate Sen. Elizabeth Warren is proposing a new tax on business groups and corporations that spend more than $500,000 annually on trying to influence the government.

Warren released details of her proposed "excessive lobbying tax" in a blog post on Medium on Wednesday. Companies and trade groups that spend between $500,000 to $1 million per year on lobbying, calculated on a quarterly basis, would pay a 35% tax on those expenditures. The tax rate would increase to 60% for expenditures above $1 million and to 75% for expenditures above $5 million.

Revenues from the tax would be placed in a new Lobbying Defense Trust Fund "dedicated to directing a surge of resources to Congress and federal agencies to fight back against the effort to bury public interest actions by the government," according to Warren. The tax is one a series of policy changes the candidate is proposing to "end lobbying as we know it."

"My new lobbying tax will make hiring armies of lobbyists significantly more expensive for the largest corporate influencers like Blue Cross Blue Shield, Boeing and Comcast," Warren said. "Sure, this may mean that some corporations and industry groups will choose to reduce their lobbying expenditures, raising less tax revenue down the road—but in that case, all the better."

Warren specifically singles out large business groups such as the U.S. Chamber of Commerce, National Association of Realtors, American Hospital Association and Pharmaceutical Research and Manufacturers of America. She blames corporate advocacy for stopping progress on a host of issues favored by the Democratic base, from action to curb climate change to an attempted crackdown on predatory payday lenders.

"Regulatory agencies are only empowered to implement public interest rules under authority granted by legislation already passed by Congress," she said. "So how is it that lobbyists are able to kill, weaken, or delay so many important efforts to implement the law?" http://bit.ly/2o0usAk

Some of the groups targeted said the tax would likely be unconstitutional. In a statement to The Hill newspaper, Neil Bradley, chief policy officer for the U.S. Chamber, said Warren "wants to tax people because she doesn't like them exercising their constitutional right to petition the government." http://bit.ly/2oQrCOo

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