Tricksters, be they in Primary School or the Oval Office have a particular diversion they use effectively.
This is to accuse another of what one has done or is about to do.
The kid in Primary School who talks about other kids stealing the cookies is probably the kid who is stealing the cookies.
The guy who shouts ‘Fake News’ is about to spew a whole heap of it.
Just as a magician whose right hand catches your eye is about to do something with his left hand so too this popular and successful diversion.
Once one becomes aware of the trick; that the one who accuses first is the culprit, this misdirection becomes a ‘tell’.
If there was a book; “The Art of The Scam” this would be a chapter.
Always look at the person who complains about others, for it is likely the offence was committed by them.