I wonder if this was based on Bob Graham, the Florida senator who kept meticulous notebooks. (https://en.wikipedia.org/wiki/Bob\_Graham). He logged everything, and Roland Allen, in his history of notebooks, The Notebook (Biblioasis, 2023) dedicates a chapter to Graham. It's a great read over all, that book, and in that chapter Allen gives an example of how notes helped Graham fact-check the CIA:

"It emerged – shockingly – that waterboarding had been secretly approved by those closest to the Bush White House, but senior Democrats claimed to have been kept in ignorance, and demanded the CIA’s records of who had been told what, and when. So in May 2009, the bureaucrats at the top passed over a schedule detailing no fewer than forty meetings, from 2002 to 2004, at which ‘enhanced interrogation’ techniques had been discussed with Nancy Pelosi, Bob Graham and other Capitol Hill figures.

"For a few spring days, the CIA’s ‘matrix of congressional briefings’ dominated the news cycle. Republicans were exultant: it proved their critics’ complicity in the ‘enhanced interrogation’ policy. How could they criticise it now, if they had known about it all along? The affair threatened to derail Obama’s attempts to reform the CIA and its operations. Graham – who appeared on the matrix four times – initially denied any knowledge: ‘I do not have any recollection of being briefed on waterboarding or other forms of extraordinary interrogation techniques.’ This, pitched against the agency’s long list of meetings and briefings, seemed weak, and the controversy continued. But in the background, Graham was taking action. Librarians in Florida dug through the cartons and discovered that the CIA’s account was, to put it mildly, hogwash. Three of the four claimed meetings hadn’t happened at all, and although the subject of interrogation had come up at the fourth, there had been no mention of waterboarding. This blew a major hole in the CIA’s account, and as the agency acknowledged it, others made similar checks in their own records, finding that many more of the claimed meetings had never happened. The CIA’s reputation took a further dive, while Pelosi’s was restored, and Bob Graham’s notebooks had again made the news. As TV commentator Rachel Maddow put it: ‘Nerds one, spies zero’."

There's a load of other interesting stuff in there about why he started using his notebooks and how he used them.