From PolitiFact:
Responsibility for Capitol security sharedCapitol security is provided by the sergeants-at-arms , who are the chief law enforcement officers for the House and Senate, in coordination with the Capitol Police, a federal law enforcement agency.
The House sergeant-at-arms reports to the speaker of the House, or Pelosi at the time of the attack. The Senate sergeant-at-arms reports to the Senate majority leader; in the days leading up to and including Jan. 6, that was Kentucky Republican Mitch McConnell.
Security of the Capitol Complex is the direct responsibility of the four-member Capitol Police Board, which includes both sergeants-at-arms, said Jane Campbell, president and CEO of the United States Capitol Historical Society.
So Pelosi, through the House Sergeant at Arms, does bear responsibility for refusing additional security measures requested by the White House.
Hmmmm...
So why didn't CNNs Tara and Holmes report that salient fact?
Did they not know, or am I asking a rhetorical question?