‘One of the most violent' Jan. 6 rioters receives a 20-year prison sentence

A Donald Trump supporter who stood in front of a gallows and spoke of his desire to hang Democratic politicians before he assaulted numerous police officers during the Jan. 6 attack on the U.S. Capitol was sentenced to 20 years in federal prison Friday.

It’s among the longest sentences handed out in a Jan. 6 case to date.

Prosecutors had sought more than 21 years (262 months) for David Dempsey, saying he “viciously” assaulted law enforcement officers at the lower west tunnel of the Capitol, where some of the worst violence took place that day.

According to prosecutors, Dempsey climbed over fellow rioters "like human scaffolding" and used "his hands, feet, flag poles, crutches, pepper spray, broken pieces of furniture, and anything else he could get his hands on" as weapons against police officers.

"Dempsey was one of the most violent rioters, during one of the most violent stretches of time, at the scene of the most violent confrontations at the Capitol on January 6, 2021," prosecutors wrote in their sentencing memo.

The 20-year sentence was imposed by Senior U.S. District Judge Royce Lamberth, a Ronald Reagan appointee who has spoken out about the “preposterous” rhetoric some Republicans have used as they attempt to “rewrite history” about the Jan. 6 attack. Lamberth has warned that “such meritless justifications of criminal activity” from politicians “could presage further danger to our country.”

Echoing his language about the “distortions and outright falsehoods” that Republican politicians have promoted about Jan. 6, Lamberth said he was concerned that Dempsey had “minimized” his conduct that day and tried to come up with non-factual justifications for his behavior. Lamberth called Dempsey’s behavior “exceptionally egregious” and said Dempsey was “dressed for battle” when he joined the mob trying to stop the peaceful transfer of power after President Joe Biden’s 2020 election victory.

“You failed, fortunately, for our country,” Lamberth said.

He added that Jan. 6 could have been even worse — “a bloodbath” — had rioters succeeded in their goal of getting to members of Congress who were certifying the presidential election results.

Witnesses in court said that Dempsey, while being led out of court, appeared to flash an “okay” gesture with his fingers that has in recent years become a symbol of white supremacy and far-right causes.

Dempsey assaulted numerous officers on Jan. 6 but pleaded guilty specifically in connection with attacks on Washington Police Detective Phuson Nguyen, whom he hit with “a torrent of pepper spray” just after another rioter compromised Nguyen’s mask, and Washington Police Sgt. Jason Mastony, who was hit so hard with a metal crutch that he collapsed in a daze and was left with a gash in his head, prosecutors wrote.

"Though Dempsey has pled guilty only for his assaults on Detective Nguyen and Sergeant Mastony, his violent assault on other officers defending the Capitol was relentless: swinging pole-like weapons more than 20 times, spraying chemical agents at least three times, hurling objects at officers at least ten times, stomping on the heads of police officers as he perched above them five times, attempting to steal a riot shield and baton, and incessantly hurling threats and insults at police while rallying other rioters to join his onslaught," prosecutors wrote.

Before he assaulted officers, Dempsey stood in front of a gallows that had been set up near the Capitol, which included a sign that said, "this is art." Dempsey, known to online sleuths as #FlagGaiterCopHater because of his American flag face covering and his assaults on officers, indicated he thought the gallows should be used to hang politicians he dubbed "worthless cretins" in video cited by prosecutors.

"String all these f---in’ worthless bastards up from the top of those," he said in the video, pointing to the gallows, "these treelines, the rafters, the rooftops, the statues, I don’t care where they go. String ’em up and string ’em up high. And let everybody know this is what happens when you are a treasonous piece of s--- who doesn’t belong in this f---in’ country and has this f---in’ country’s worst objective at heart."

Dempsey was arrested in connection with the Capitol attack in August 2021 and had previously been charged in 2019 with dousing demonstrators in California with bear spray while he wore a "Make America Great Again" hat; he pleaded no contest in that case. He pleaded guilty in his Capitol attack case on Jan. 4.

Dempsey, who prosecutors say is a former construction worker and fast-food employee with a "very significant history of arrests and convictions," was identified with the help of online sleuths who have aided the FBI in hundreds of cases against Jan. 6 rioters. Federal prosecutors say that in addition to assaulting anti-Trump protesters with bear spray in 2019, resulting in a two-year suspended sentence, he previously assaulted a counterprotester with a skateboard in a separate incident in 2019, used the same skateboard to assault another person at a political protest in 2020 and hit a person with a metal bat during another 2020 protest.

More than 1,400 people have been arrested in connection with the Jan. 6 attack, and prosecutors have secured more than 1,000 convictions. Hundreds of defendants have received probationary sentences, but more than 560 defendants have been sentenced to periods of incarceration ranging from a few days behind bars to 22 years in federal prison.

This story first appeared on NBCNews.com. More from NBC News:

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