Doug Hughes flew his gyrocopter onto the south west lawn of the Capitol on April 15. (Alfredo Duarte/for El Tiempo Latino)

The Florida postal worker who landed a gyrocopter at the U.S. Capitol to protest campaign finance laws will plead guilty to reduced charges this month under an agreement with prosecutors, his attorney said Friday.

Douglas Hughes, 61, of Ruskin, Fla., will admit to one felony count of operating a gyrocopter without a license, attorney Mark L. Goldstone said. Although the offense is punishable by up to three years in prison, Goldstone said, the two sides agreed that no sentencing guideline applies, leaving a judge free to go lower.

Bill Miller, a spokesman for the U.S. attorney’s office for the District, said in a statement, “We typically do not comment on the possibility of pleas in our cases and have no comment regarding this particular matter.”

A hearing is set for Nov. 20 before U.S. District Judge Colleen Kollar-Kotelly.

The plea would not be final until the hearing is concluded, and defendants sometimes change their minds. A judge also must approve the plea.

Doug Hughes said he intended to deliver letters of protest to Congress by flying a small gyrocopter through the no-fly zone and landing at the Capitol. (Borchuck, James/Tampa Bay Times)

In a statement, Goldstone said, “Doug Hughes will continue to be a strong voice for campaign finance reform and getting excessive money out of politics and allowing all citizens regardless of the size of their bank accounts a voice in our democracy.”

Hughes was indicted in May and pleaded not guilty to six felony and misdemeanor counts after flying his low-power gyrocopter from Gettysburg, Pa., to the District on April 15. If convicted of the original charges, he would have faced a sentence of up to 9 1 / 2 years in prison.

Hughes’s plea deal, first reported by the Associated Press, would resolve a case that his supporters hoped would spotlight what they say is the corrupting role of money in politics. But to prosecutors, the case presented a puzzle: How to punish this novel act of aerial civil disobedience.

Piloting what was described as a flying lawn chair powered by a small motor-driven propeller through restricted airspace over the nation’s capital, Hughes said he was delivering letters to members of Congress urging them to pass reforms.

Hughes refused prosecutors’ initial proposal that he plead to reduced charges and face a recommended 10-month prison sentence, saying his action caused no injury or damage. His attorneys argued that a zero-to-six-month recommendation or a period of home confinement would be appropriate.

Prosecutors said Hughes’s actions were reckless and endangered his life and others. But they said they could not find any prior prosecutions under the statutes used to charge Hughes.

A member of the U.S. Capitol Police Bomb Squad works to check and secure a gyrocopter that landed on the lawn. (Chip Somodevilla/Getty Images)

U.S. probation officials recently reported that they could not find any applicable case to guide a possible sentencing recommendation to the court, saying their best guess at a comparable offense is trespassing.

Hughes was indicted for felony counts of operating without a pilot’s license and aircraft registration, three misdemeanor counts of violating national defense airspace and one misdemeanor count of operating a vehicle falsely labeled as a postal carrier.