(CNN) You'd expect partisan questions about a politician's sanity, but now there's an unusual debate growing among licensed mental health professionals about President Donald Trump.

The United States' major mental health associations -- including the American Psychiatric Association, which claims to be the largest psychiatric association in the world -- are warning members not to wade into the debate, but some prominent doctors have done just that, publicly voicing concerns and questioning the very ethics of their profession.

For the psychiatrists, it's all spelled out in section 7.3 of the American Psychiatry Association's code of ethics a set of guiding best-practice principles for members -- who make up most licensed psychiatrists. The section is informally known as the "Goldwater Rule" because it came about after what the association's president calls a "very public ethical misstep" by psychiatrists who answered a survey about another Republican, presidential candidate Barry Goldwater.

Details about the survey were published in a pre-election 1964 article in a now-defunct magazine called Fact. Of the 2,417 psychiatrists who answered the survey, the majority concluded that Goldwater was "psychologically unfit" to be president.

In the 38 pages of psychiatrists' comments, some said they could not diagnose him "by merely observing him on TV or reading what he writes," but those who were critical of Goldwater labeled the candidate in unflattering terms, calling him a "dangerous lunatic," "paranoid" and a "counterfeit figure of a masculine man." Some accused him of having an "impulsive quality," said he was "emotionally too unstable" and said he had a "Godlike self-image."

After Goldwater lost the election, he sued the magazine's editor for libel and won his case. The editor appealed the decision all the way to the Supreme Court , but the justices declined to hear it. In one of the two dissenting opinions, Justice Hugo Black wrote that "the public has an unqualified right to have the character and fitness of anyone who aspires to the Presidency held up for the closest scrutiny."

That "closest scrutiny" shouldn't come from psychiatrists who did not evaluate the figure in person, the American Psychiatric Association decided, and in 1973, the Goldwater Rule became a part of its code of ethics.

The rule states: "On occasion psychiatrists are asked for an opinion about an individual who is in the light of public attention or who has disclosed information about himself/herself through public media. In such circumstances, a psychiatrist may share with the public his or her expertise about psychiatric issues in general. However, it is unethical for a psychiatrist to offer a professional opinion unless he or she has conductedf an examination and has been granted proper authorization for such a statement."

Psychiatrists, medical doctors who can prescribe medications, differ from psychologists and have separate organizations. Psychologists are not medical doctors -- typically, they have Ph.D.s -- but they may also be called upon to lend expertise about the mind and behavior of some public figures.

Psychologists don't have a Goldwater Rule per se, but the American Psychological Association code of ethics also warns members against diagnosing any person, including public figures, whom they have not examined personally. The president of that association also wrote about the guidelines during the 2016 election cycle

Does Trump trump the Goldwater Rule?

In August, American Psychiatric Association President Dr. Maria Oquendo reminded members of the Goldwater Rule, since she suspected that they "may be goaded into talking or tempted to talk" to the media about the candidates' mental health.

"The unique atmosphere of the year's election cycle may lead some to want to psychologize the candidates, but to do so would not only be unethical, it would be irresponsible," Oquendo wrote on the association's website

Since then, she said, she has received countless letters and postcards from members who questioned whether "we should adhere to this very old rule that is more than 40 years old," she said.

The association's ethics committee is revisiting the issue, she said, but she doesn't anticipate any change.

"It is just as valid as it was in 1973," Oquendo said.

She believes that giving a detailed mental evaluation is key to rendering the right professional opinion. Without it, what someone says in public could be misinterpreted. Someone with a blood sugar problem could sound incoherent, for instance, and be misdiagnosed.

biology of mental disorders and other medical ethics issues. "That's not enough of a reason to keep silent to support this rule," said Dr. Claire Pouncey, a psychiatrist and philosopher in Philadelphia who has lectured about the Goldwater Rule and has written about it in professional publications . Congress has even consulted her on ethical issues related to thebiology of mental disorders and other medical ethics issues.

"We are talking about patterns of public behavior; besides, we have that whole one-page testimony (from Trump's personal physician) that he doesn't have problems with blood sugar or thyroid disease."

Though Pouncey said she upholds the Goldwater Rule, she believes it is too restrictive.

"We get diagnoses wrong all the time, even with people we work closely with, but when you see a demonstrated pattern of behavior repeated over time, that as trained professionals we are sensitive to, it is not unethical to speak out," she said.

A 'Rule' meant to be broken, some say

Certainly not all mental health professionals are following their associations' directives. Last week, 35 prominent mental health experts signed a letter of dissent to the New York Times.

"We fear that too much is at stake to be silent any longer," the letter states. Trump's speech and actions show that he has an "inability to tolerate views different from his own, leading to rage reactions" in which he is unable to empathize, and he is "attacking facts and those who convey them."

The letter warns that Trump's attacks will probably increase and that the "grave emotional instability" shown by his actions and words "makes him incapable of serving safely as president."

Among those signing the letter was Dr. Leonard Glass, a part-time associate professor of psychiatry at Harvard Medical School and works as a senior attending psychiatrist at McLean Hospital in Belmont, Massachusetts. Generally, he believes, there is merit to the Goldwater Rule. It keeps members "from using their professional standing and their credentials and plausibility, to expound about figures in an ill-informed way."

But in this case, he doesn't see anything wrong with professionals sharing their opinions, which don't require a specific diagnosis, especially in this "extraordinarily unprecedented situation."

The Goldwater Rule has come into question long before this president was elected.

Pouncey co-authored an analysis and commentary published in the Journal of the American Academy of Psychiatry and the Law last year, though it was written several years before. It argued that in general, the Goldwater Rule was "excessive" and "not only unnecessary," it "detracts from the deeper dictates of ethics and professionalism."

The guidelines encourage psychiatrists to participate in public education, creating "a mandate for psychiatrists to engage in rather than refrain from commentary when public figures seem to pose a risk to community safety."

Co-author Dr. Jerome Kroll said they hadn't written the paper with Trump in mind, but they do think it is relevant in this case. He thinks the American Psychiatric Association is wrong.

"Our voices shouldn't be stifled, and our profession should step up," Kroll said.

Kroll, a professor emeritus in the Department of Psychiatry at the University of Minnesota, works with a large number of Somali refugees who are deeply worried about the president's immigration policies.

Although the Goldwater Rule calls for a complete evaluation, Kroll doesn't think he'd get any more insight in person than from what he sees of Trump on television.

"If I sat in alone with him in a room for a two-hour assessment, I am not going to kid myself that he would tell me the truth," Kroll said.

But Kroll acknowledges there are limits to this kind of observation.

"We can't always tell what is showmanship and what is meant when he says, 'this country is terrible, and I'm the only one who can fix it,' " Kroll said. "Is this narcissism, or is he just bullshitting the audience?"

It is this ambiguity that makes Dr. Mike Redinger think the Goldwater Rule should apply.

"A public figure or performer shows you the image they want to portray," said Redinger, assistant professor of medical ethics, humanities, law and psychiatry at Western Michigan University Homer Stryker M.D. School of Medicine. He co-authored a critical response to Kroll and Pouncey's journal article about the Goldwater Rule . "It is hard to know what reflects their internal thoughts and beliefs and what is for show."

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Redinger believes one could get an "unvarnished assessment of Trump's internal thinking" with an in-person assessment. Without that, out of an abundance of caution, a psychiatrist should not diagnose someone from afar, since it could be "inaccurate and damaging to the person's reputation."

The psychiatric association's Oquendo added that although everyone is free to make observations about a person's behavior, this rule remains vital for her profession.

"One of the underlying assumptions behind wanting to render a diagnosis is, if someone has a psychiatric condition, they are not fit to serve, by definition," she said. "This is a very murky and risky area."