Washington (CNN) The Florida man who allegedly piloted a gyrocopter onto the Capitol grounds last month to protest big money in politics has been indicted by a federal grand jury on six charges, which could land him nine-and-a-half years in prison if he's convicted on all counts.

Doug Hughes, a 61-year-old mailman from Ruskin, Florida, caused a stir at the Capitol when he landed a small manned aircraft on the West Lawn in violation of multiple no-fly zones and without having notified authorities of his plans.

Hughes quite literally planned to send a message to Congress and the rest of America in protest of the Citizens United Supreme Court decision that paved the way for super PACs and unlimited amounts of money to pour into political campaigns -- he carried letters for every member of Congress urging them to reform campaign finance laws.

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On Wednesday, a grand jury indicted him on two felony counts -- one count of "operating as an airman without an airman's certificate" and another count of "violating registration requirements involving aircraft," according to a release from the D.C. U.S. Attorney's office, which said an investigation had determined that he has no pilot's license or registration for the craft.

He also faces four misdemeanor charges: Three counts of "violation of national defense airspace" and one of "operating a vehicle falsely labeled as a postal carrier." His arraignment is scheduled for Thursday at the D.C. District Court.

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