Capitol Police officer recounts Jan. 6 attack: Exclusive

The first time Harry Dunn stepped inside the U.S. Capitol also happened to be his first day as a Capitol Police officer.

“The rotunda … you just look up and it just goes up forever -- it's just an amazing architectural building,” Officer Dunn told ABC News’ Chief Justice Correspondent Pierre Thomas. “It's hard to not be in awe of it when you see it.”

Dunn said the rotunda no longer resembled the room he once knew on Jan. 6, the day of the siege on the Capitol.

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“This time you look up, it's just a cloud of smoke, fire extinguishers have been going off,” Dunn recalled walking into the room soon after fighting off a mob of angry rioters. “The floors are covered in white dust, water bottles, broken flagpoles, mask, empty canisters of pepper spray, helmets, Trump flags, everything in the rotunda, just laying there on the floor.”

Dunn recalls gasping for air through the pepper spray and bear mace, blood on his knuckles and the relentless noises from the rioters. He soon found himself in tears, being consoled by a fellow officer who asked him what had happened amidst the chaos.

"’I got called a [N-word] a couple dozen times today protecting this building,’” Dunn recalled telling his colleague. “Is this America? They beat police officers with Blue Lives Matter flags. They fought us, they had Confederate flags in the U.S. Capitol.”

Dunn is a 13-year veteran in the U.S. Capitol Police Department. Speaking only for himself and not the department, Dunn is the first U.S. Capitol Police officer to speak publicly about the events of Jan. 6.

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The exclusive interview aired Monday morning on "Good Morning America" and will air again next Tuesday at 10 p.m. ET on a new ABC News primetime magazine called "Soul of a Nation," a series that examines the Black lived experience in America.

During former President Donald Trump's second impeachment hearing, Rep. Jamie Raskin, D-Md., quoted Dunn from a Buzzfeed article, in which Dunn shared his story anonymously a few days after the insurrection.

“Is this America?” said Rep. Raskin, echoing Dunn’s words on the Senate floor.

“It took me back to a dark place because I didn't say it for a catchphrase -- I wasn't trying to create a slogan,” said Dunn. “I struggle… should I be proud? No, not at all.”

Dunn does not know if his words were effective during the trial, but he wishes they did not have to be said at all.

“Those were my feelings and that was my truth -- it wasn't a proud moment. It took me back to a dark place," he said.

Dunn does not mince words when describing the pro-Trump rioters who stormed the Capitol.

“They were terrorists,” Dunn told ABC News. “They tried to disrupt this country's democracy -- that was their goal... And you know what? Y'all failed because later that night, they went on and they certified the election.”

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Dunn praised his fellow officers, including officer Brian Sicknick, who died during the insurrection -- describing him as a “brave” and “dedicated officer. Dunn also lent praise to officer Eugene Goodman, whose heroics were caught on camera that day.

“There were dozens of Eugene Goodmans that day,” said Dunn. “Eugene got caught on camera and I'm not surprised that he did the right thing, the brave thing, the heroic thing -- there were so many Eugene Goodmans that weren't caught on camera that day. … and I'm proud to work with all of them.”

The Capitol Police Department has fallen under scrutiny since the attack. Many are questioning whether there was a lack of preparedness and the actions taken, or not taken, from top management in the days and moments leading up to the Jan. 6 attack.

The Capitol Police Office of Professional Responsibility is investigating 35 Capitol Police officers for their actions on Jan. 6, according to a statement issued by the department. Six officers have been suspended with pay and Acting Chief Yogananda Pittman has directed that members of the department whose behavior is not in keeping with the Capitol Police rules of conduct will “face appropriate discipline,” the statement said.

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Former Capitol Police Chief Steven Sund, Metropolitan Police Chief Robert Contee, former Senate Sergeant at Arms Michael Stenger and former House Sergeant at Arms Paul Irving are expected to appear before a Senate hearing in what will be the first public testimony on the Capitol breach to date.

Pittman is scheduled to appear before a House Appropriations Committee on Thursday.

“Everybody wants to know what could have been done differently, because that shouldn't have happened,” said Dunn. “[I’ll] wait for the investigation to be completed officially and not draw conclusions about something of this magnitude -- I'll just leave it at that.”

ABC News' Jack Date contributed to this report.