Dr. Drew Pinsky: Trump may be mentally ill — so what does that say about his supporters?

Donald Trump's opponents have been wondering what psychological disorders might explain the Republican presidential nominee's erratic behavior -- but Dr. Drew Pinsky is more curious about why his supporters are willing to overlook those warning signs.

The physician and media personality appeared Monday night on CNN, where he told Don Lemon that Trump does not fit the stringent legal definition for insanity -- but he does show signs of multiple mental illnesses.

"There's two definitions of sanity, one is legal definition, and that is somebody who is so out of it they don't know the difference between right and wrong," Pinsky told CNN's Don Lemon. "That is a very high standard for insanity, (and) very few people meet that standard. When you're legally insane, you're really not functioning. Clinically, medically, usually when we talk about insanity, we mean psychotic, hearing voices, hallucinations."

He told Lemon that Trump did not fit either the legal or clinical definition of insane, and then he discussed the candidate's apparent narcissism.

"People want to label him with a narcissistic personality disorder, and that is a pretty tough, tough thing to do at a distance," Pinsky said. "But let me just talk to you, narcissism generally can be a good thing. If you're a fighter pilot, we want you to be narcissist, not to have fear in extreme circumstances. Most political leaders have some degree of narcissism, what motivates them to go into these areas. We've done research on this, (and) it bears that out."

Pinsky disagreed with HBO host John Oliver's assessment that Trump was a sociopath, saying the real estate developer and reality TV host appeared to maintain close relationships with his children.

"It is unfair because sociopaths are usually tied up with really, serious problems with criminal behavior, but, you know, you can be manipulative, can be narcissistic and still do okay in life," Pinsky said. "But, again, your relationships usually have extreme pathology. (It's) very difficult to raise healthy kids, very difficult to have sustained marriages if you're deep into narcissism."

However, he said Trump showed enough troubling signs of mental instability to raise concerns about his fitness for office.

"The question, though, is, are some of the reckless qualities that everyone is getting so disturbed about on the campaign going to be translated into office should he get elected?" Pinsky said. "That's a pretty hard thing to predict. I don't know if this is just somebody playing politics, or is this somebody who really can't contain their impulses?"

Pinsky wondered if Trump might show signs of bipolar disorder, which is characterized by unusual shifts in mood, energy and activity levels, along with an inability to carry out daily functions.

"When I hear people that are impulsive with their speech, I worry about hypomania and bipolar types of conditions," Pinsky said. "As he says, he has boundless energy. Again, a little hypomania can be great. There are a lot of hypomanic businessmen that get a ton done. Containing your speech, be thoughtful, take a beat before you say something, for those people it can be very, very difficult."

Pinsky said he was more interested in Trump's supporters than the candidate himself.

"What's more fascinating to me, Don, is not him but his supporters that seem to not be concerned about any of this," Pinsky said. "That, to me, is fascinating. As always, what is up with us?"

His strongest supporters seem not to care about Trump's outrageous insults against a Gold Star family -- or anyone else -- and even the candidate himself seems impervious to shame.

"Let's just assume that most people that would choose to be in a very high-profile race like this would have narcissistic tendencies, and there's something called sort of narcissistic injury, then narcissistic rage," Pinsky said. "If you injure -- if you really shame somebody -- they tend to be sort of teflon when it comes to shame. If you shame them, they can react with extreme aggression and extreme rage. So this seems to be that kind of a psychological process."

Pinksy said he wondered why that trait seemed to appeal to so many voters.

"I have a radio program on KABC, (and) what I keep hearing from listeners there is enough is enough," Pinsky said. "If somebody is going to fight back, they're going to say, whatever, and I don't care what he says as long as it's extreme and pushing back and he's putting my country and my job first, I'll get behind him whatever he says. There's disregard for the content."

He said Trump's candidacy was symptomatic of broader cultural tendencies.

"Why we watch reality television?" said Pinsky, himself a reality TV star. "Why do we do this? Let's examine that."