Then-House Speaker, Nancy Pelosi (D- Calif.) & others claimed that there was a failure of leadership [Sund, a police officer for over 30 years] at the top

Americans aren’t allowed to ask questions about the events of Jan 6. So I won’t.
I will leave these comments from the Head of the Capital Police to comment. https://t.co/gLzfVEY1f1

— Rob Schneider (@RobSchneider) August 5, 2023

Some excerpts,

Sund, a police officer for over 30 years, had been head of the U.S. Capitol Police from 2019 through the protests, but resigned Jan. 7 amid claims by then-House Speaker Nancy Pelosi (D-Calif.) and others that "there was a failure of leadership at the top."

In February 2021, Sund penned a letter to Pelosi and other congressional leaders, noting, "Perfect hindsight does not change the fact that nothing in our collective experience or our intelligence – including intelligence provided by FBI, Secret Service, Department of Homeland Security (DHS) and D.C. Metropolitan Police (MPD) – indicated that a well-coordinated, armed assault on the Capitol might occur on Jan. 6."

Sund told WTTG-TV that he had asked House and Senate security officials for their permission to bring in the National Guard days ahead of the protests, but was denied. He also indicated he had asked for the National Guard several more times during the protests, but was repeatedly denied until their ultimate arrival at 5:40 p.m. on Jan. 6.

"Everything appears to be a cover-up," continued Sund. "Like I said, I’m not a conspiracy theorist, but when you look at the information and intelligence they had, the military had, it’s all watered down. ... I’m not getting intelligence, I’m denied any support from National Guard in advance. I’m denied National Guard while we’re under attack for 71 minutes."