Establishment media outlets including CNN and MSNBC have helped mainstream a conspiracy theory claiming President Donald Trump is mentally ill.

At the center of the conspiracy theory is Yale psychiatry professor Bandy Lee, who for over a year has claimed that Trump is mentally impaired and unfit to serve, pointing at his tweets as evidence.

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Three days after Lee’s book came out, the APA issued a statement reaffirming the importance of the Goldwater Rule, which instructs physicians “not to provide professional opinions in the media about the mental health of someone they have not personally examined and without patient consent or other legal authority.”

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Reporters brought up the allegations at the White House press briefing on both Wednesday and Thursday. MSNBC and CNN both gave considerable airtime on Thursday to Lee’s allegations about the president, and interviewed Democratic lawmakers about Lee’s claims. Both networks treated Lee’s accusations as credible.

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