William M. Sywak, 46, of Hamburg, and his son William J. Sywak, 28, of Arcade, pleaded guilty Wednesday in U.S. District Court in Washington, D.C., to parading, demonstrating or picketing in a Capitol building, a misdemeanor. They were initially charged with three other counts: knowingly entering any restricted building or grounds; impeding or disrupting the orderly conduct of government business; and disorderly conduct on Capitol grounds.

"He totally regrets having gone into the Capitol," said attorney Herbert L. Greenman, who represents the father.

"He's strongly remorseful for what he did," Greenman said. "He never had any real malice to do anything that would cause any damage or hurt anybody."

William J. Sywak, the son, is also remorseful and embarrassed, said his lawyer, Mary Beth Covert.

"He pled guilty and recognizes what he did was inappropriate, and he just wants to put it behind him," Covert said.

Both the father and son signed documents acknowledging their conduct during the Jan. 6 storming of the Capitol, and those documents detail the timing and locations of what the two did when thousands of people swarmed around and in the Capitol with hundreds attacking and injuring police officers.

The two are among the approximately 640 defendants who were charged with entering or remaining in a restricted federal building or grounds, according to U.S. Attorney's Office in Washington. The Sywaks were not among the more than 225 defendants charged with assaulting, resisting or impeding officers or employees, including more than 75 individuals who have been charged with using a deadly or dangerous weapon or causing serious bodily injury to a police officer. Approximately 140 police officers were assaulted Jan. 6 at the Capitol.

The Sywaks traveled together by car to Washington to attend the "Stop the Steal" rally, arriving at around 1 p.m. They missed then-President Trump's speech, so they went to the Capitol grounds, according to their plea documents.

At 2:18 p.m., five minutes after rioters first breached the Capitol through the Senate wing door, the Sywaks entered the Capitol and then made their way toward the crypt, a vaulted large circular room beneath the rotunda.

Soon the two were separated.

The son remained inside the Capitol for about 20 minutes before leaving at 2:40 p.m. After exiting, he made his way toward the lower west plaza, where he joined a group of rioters close to the police line, as officers were instructing the crowd, including Sywak, to clear out and move back, according to a court document. During the riot, the son also made his way to the northeast courtyard and up the stairs leading to the Columbus Doors on the east side of the building, where he video-recorded a large crowd attempting to breach the eastern doors leading into the Capitol rotunda.

At around 4:36 p.m., Sywak texted a close associate, "this election is terrible an[d] they need to know (expletive) gotta be taken seriously."

The father also remained inside the Capitol for about 20 minutes, leaving at approximately 2:41 p.m.

On Jan. 7, after returning home, the son texted an associate to describe his experience at the riot: "Things I seen was aw[e]some people handing me pepper spray to get into the push."

His messages described other rioters wielding chemical spray that "over powered that police pepper spray" and were targeting "right into a cops eyes." He stated, "The people will not give up an[d] that's what we were showing them the capital is the people house not the governemts they work for us."

Sywak and his son were identified as suspects in late January when investigators at the FBI Washington Field Office found a match between a photo of the elder Sywak on the grounds of the Capitol and a mugshot from a prior arrest.

When FBI agents interviewed the father on Jan. 27, he at first denied going into the building and said that after arriving at the Capitol grounds he and his son got separated, according to the criminal complaint filed against him. The father told the FBI that his cellphone battery died and he was unable to locate his son. He also said his son didn't go into the building or commit violent acts.

But when an agent showed the father a photo of him from the Capitol, he said, "Yeah, that's me," according to court documents.

Later the FBI reviewed video posted to YouTube that shows a man resembling the father exiting a doorway manned by Capitol police officers. FBI agents also found closed-circuit TV footage of a person who appeared to be the father exiting the Capitol.

FBI agents said they matched a photo of the son posted on Facebook to bodycam video from a D.C. Metropolitan police officer outside the Capitol and to surveillance camera footage inside the building that shows him holding up a cellphone.

Greenman said his client, the father, intended only to listen to Trump at the rally.

"His intention was to get down there and only hear the president speak. And that was it," Greenman said. "But he missed the entire speech.

"He never intended to do this until he got right to the steps," Greenman said of the father entering the Capitol. 

"He went down there because he was interested in what the president was going to say," he said. "He wishes he had never gone."

Sentencing is set for June 6 before Judge Rudolph Contreras. Both Sywaks, who have been free on personal recognizance bond since their arrests, can appear at their sentencings by video.

Sentencing guidelines call for up to six months in prison, five years of probation and a fine of up to $5,000.

"We don’t have any promises," Greenman said of the prospective sentence. "What we want to do is convince the judge that this is a guy who has a lot of contrition, a lot of feelings of remorse and a guy who certainly is not the kind of person who would ever do anything like this ever again. He's had plenty of time to think about it. He's gone through a lot. He's taken this entire case very seriously."