Former U.S. Capitol Police Chief Terrance Gainer said he wants to give police "the benefit of the doubt" and hopes they were attempting to de-escalate Wednesday's event when they appeared to let pro-Trump rioters inside the legislative building.
"Sometimes when you don't have enough personnel, you can't stand and fight a large crowd like that," he said on NBC's "Today" show Thursday, noting that there were not enough law enforcement personnel on scene.
A ceremonial event at the Capitol affirming that President-elect Joe Biden won the November election was abruptly paused Wednesday afternoon after hundreds of rioters stormed inside.
Congress members and Vice President Mike Pence had to seek shelter. A woman was fatally shot by police during the chaos and three others died in "medical emergencies," according to Washington Police Chief Robert Contee.
In the midst of the riot, videos surfaced of police appearing to let the protesters inside the building. One video appeared to show a man taking a selfie with an officer.
Gainer, who served as Capitol Police Chief from 2002 to 2006 and was the Senate sergeant-at-arms, said the police's handling of the situation was "a failure" and "raises a lot of questions."
"Clearly there's failures," he said. "There has to be a lot of questions asked and answers given. What is very clear is the police underestimated the violent crowd and the size of it, and they overestimated their ability to control it."
Capitol Police Chief Steven Sund commended officers for their "heroic" actions and slammed the chaos that erupted as "criminal riotous behavior." He said in a statement on Thursday that more than 50 capitol police and Metropolitan Police Department officers were injured, with several hospitalized with serious injuries.
"United States Capitol Police officers and our law enforcement partners responded valiantly when faced with thousands of individuals involved in violent riotous actions as they stormed the United States Capitol Building," he said. "The violent attack on the U.S. Capitol was unlike any I have ever experienced in my 30 years in law enforcement here in Washington, D.C."
The statement did not address the videos and photos of officers.
Bill Bratton, the former commissioner of the New York Police Department and an NBC News analyst, said there needs to be an explanation about why the crowd was able to get inside. "Right now the appearance of it looks awful," he said.
Many law enforcement officials around the country questioned how police failed to protect the building.
Gainer said on "Today" that he had always thought it would be impossible to storm the Capitol. The last major breach of the Capitol happened during the war of 1812.
Photos from the riot showed some lawmakers praying as demonstrators ran amok inside the building, many of them carrying pro-Trump banners and some waving Confederate flags. A photo surfaced of a noose hanging on the west side of the Capitol.
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Windows inside the building were smashed and doors were battered down. Some of the rioters were pictured seated in the Senate chamber and Congress members' private offices.
Two devices were found after police received reports of a pipe bomb. Chief Sund said that the devices were determined to be "hazardous" and were disabled and turned over to the FBI. A suspicious vehicle was also found and its driver was arrested.
Thirteen other people were taken into custody for unlawfully entering the Capitol, Sund said.
The National Guard, FBI and U.S. Marshals Service were all called in to assist. Washington Mayor Muriel Bowser ordered a 12-hour curfew in the city that ended at 6 a.m. Thursday.