Cassidy Hutchinson, who filled in as a senior helper to Trump White House 

White House head of staff Mark Meadows

Tuesday at a somewhat late hearing planned by the Jan. 6 panel, three sources tell NBC News.

In recorded declaration introduced last week

 Hutchinson let examiners know that a gathering of GOP legislators had looked for official exculpations 

The revolt at the Capitol, including Reps. Matt Gaetz of Florida and Mo Brooks of Alabama.

Hutchinson and her lawyer didn't answer a solicitation for input Monday.

The panel unexpectedly announced Monday that it would hold a hearing 

Tuesday to present new evidence and hear witness testimony

 But did not specify who would be offering testimony like it did for previous hearings.

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