"Whenever the Vice President and a majority of either the principal officers of the executive departments or of such other body as Congress may by law provide, transmit to the President pro tempore of the Senate and the Speaker of the House of Representatives their written declaration that the President is unable to discharge the powers and duties of his office, the Vice President shall immediately assume the powers and duties of the office as Acting President."To the Democrats, "unable to discharge the powers and duties" means having Trump declared "mentally unfit". Then the plan would be to pressure the Vice President and a majority of his cabinet to act in accordance with the above text of the 25th Amendment. Many see Vice President Mike Pence as a more reasonable alternative than Trump and his dismantling of decades of liberal progress.
Representative Ted Lieu, a California Democrat, has even proposed legislation that would force Trump to have a "psych eval". This fact was published in an opinion piece in the New York Times titled: "Is It Time to Call Trump Mentally Ill?" That "piece" was written by Professor of Clinical Psychiatry Richard A. Friedman at Weill Cornell Medical College. No word as to who he voted for, but chances are he's a Hillary fan. In that same "Times" article, he listed other instances where "psychiatrists" have questioned Trump's mental "stability". Friedman also noted that the American Psychiatric Association requires its members to practice what is the "Goldwater Rule", which states that "it is unethical for them to diagnose mental illnesses in people they have not examined and whose consent they have not received." Still, Democrats seem to think that they are competent to judge Trump's sanity; simply by what he says.
So, all these claims of mental illness are going nowhere unless Trump, himself, "consents" to a clinical examination(s). Something I doubt will ever happen. Even if he did, who would conduct such an exam? Democrat Senator Schumer? I'm sure his law degree makes him eminently qualified. In addition, under the patient protections of the HIPAA law, the findings of any examination cannot be made public without Trump's approval. Further, do you really think the Vice President and Cabinet Members, hand-picked by Donald Trump, would turn on him?
For sure, the anti-Trump protestors are going to incorporate what they see as signs of "mental illness" into their protest events. Perhaps they would find a march on October 10th, World Mental Health Day, to be appropriate. Of course, their plan is to oust Trump long before that.
Keith Olbermann Has a Surprisingly Simple Way to Oust Donald Trump – WATCH: http://www.towleroad.com/2016/11/keith-olbermann-surprisingly-simple-way-oust-donald-trump-watch/
Twenty-fifth Amendment to the United States Constitution: https://en.wikipedia.org/wiki/Twenty-fifth_Amendment_to_the_United_States_Constitution
Is It Time to Call Trump Mentally Ill? https://www.nytimes.com/2017/02/17/opinion/is-it-time-to-call-trump-mentally-ill.html
Democrats Go There: Invoke 25th Amendment Unless Trump "Gets A Grip": http://www.zerohedge.com/news/2017-02-19/democrats-go-there-invoke-25th-amendment-unless-trump-gets-grip
25th Amendment Could Declare Trump Mentally Unfit: https://www.yahoo.com/news/25th-amendment-could-declare-trump-163732166.html
How Can We Get Rid of Trump? https://www.nytimes.com/2017/02/18/opinion/sunday/how-can-we-get-rid-of-trump.html?ref=opinion
HIPAA Privacy Rule and Sharing Information Related to Mental Health: https://www.hhs.gov/hipaa/for-professionals/special-topics/mental-health/