“Correcting people can actually make factual perception worse,” says a Georgia State University professor on the panel. In other words, if you tell a supporter of Candidate A that s/he is blatantly lying, they may support that candidate more.
He says it’s because peoples’ sense of selves and self-esteem are bound up with their worldviews. Thus, attack their candidate, and you’re attacking their self-image. Cognitive dissonance kicks in.