Research suggests a candidate’s likelihood of being elected can be predicted by their appearance, which is often judged in milliseconds.

The democratic process is supposed to hinge on the public’s sound decision-making ability to gauge political candidates.

Unfortunately, it doesn’t always work out that way.

While most people believe they are a good judge of character, voters can make up their minds about a political candidate in a matter of milliseconds — even without a speck of insight on that candidate’s beliefs or policies.

An online poll of 116 Healthline readers showed 55 percent of respondents believe Democratic presidential candidate, Hillary Clinton, has a more trustworthy face than her Republican counterpart, Donald Trump. Of those who responded, 74 percent were over the age of 45, and 76 percent were female.

While these results aren’t scientific, they highlight how some candidates can have innate advantages over others.

But as new research suggests, that can dramatically backfire.

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If you’ve already picked your candidate for the 45th president of the United States, it may not have been a conscious choice.

Your mind may have made itself up long ago.

Political rhetoric aside, to win the hearts and minds of voters, the two major presidential candidates have to compete at an underlying psychological level.

Stephen Porter, Ph.D., a psychology professor at the University of British Columbia (UBC), and Ph.D. student Alysha Baker, speculate that Clinton may have the upper hand when it comes to perceived trustworthiness.

“For example, features that may help her be perceived as trustworthy include a round face and relatively large eyes,” the pair told Healthline. “On the other hand, Trump’s furrowed eyebrows would likely feed into an untrustworthy-looking assessment, for example.”

These perceptions could be engrained survival instincts. Being able to quickly assess whether a new face is that of a friend or a foe is an intuitive way to determine if an outsider is approaching to do harm.

Certain facial features, such as higher eyebrows, more pronounced cheekbones, and a rounder face are considered to make an individual look more trustworthy. The opposite — downturned eyebrows or a thinner face — can make a person seem less trustworthy.

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Porter and Baker recently published their findings from two studies that assessed how these slight differences in facial features can make a large impact in perceiving someone as trustworthy.

In the studies, participants watched a video, listened to audio-only pleas, or examined a photo of people publicly asking for the return of a missing relative. The study subjects were asked about their personal perceptions of general trustworthiness and honesty.

The examples used were real life criminal cases: an 81-year-old woman pleading for justice for her husband’s killer, and a father pleading for the return of his missing 9-year-old daughter.

Overall, subjects believed the elderly woman, and assumed the father was lying. In reality, the father was innocent, and the woman had murdered her husband.

Their findings, published in the journal Psychology, Crime & Law, highlight the implications of these kinds of biases. In the legal setting, someone perceived as untrustworthy may be judged more harshly and receive a harsher sentence.

While their studies focused on the criminal justice system, Porter and Baker say their research has obvious implications in the political realm. They say research has shown that politicians who look both competent and trustworthy are more likely to be elected than those who lack such facial features.

“And we expect that more trustworthy-looking politicians will be more easily believed,” they said. “Take, for example, Bill Clinton, who has a competent and trustworthy-looking face. He is far more likely to be believed when saying, ‘I did not have sex with that woman,’ than a politician who looks untrustworthy.”

The official record, however, tells its own story.

While nonverbal clues can be faked — such as a psychopath mimicking expressions of happiness or empathy — Porter and Baker said no one is able to manipulate how competent his or her face looks.

When it comes to trustworthiness, it’s all about the jaw, cheeks, and upper face, an area where Trump, generally, is behind in the polls.

“In many of the images we have looked at of Clinton, she expresses an incomplete smile in which the lower half of her face looks happy but her eye region does not, a fake smile so to speak,” they said. “In many of the images we see of Trump, he appears angered or contemptuous. So both are at a disadvantage in terms of facial expressions. But in general Clinton has the upper hand just in terms of her facial structure.”

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While it seems shallow to pick a political candidate based on his or her facial appearance, it’s a reality, even without our conscious knowledge.

Research stemming as far back as the 1970s has shown that all it takes is a photograph to accurately predetermine the winner in Senate, House, and gubernatorial elections.

The field of cognitive psychology explores how the mind tends to oversimplify the decision process. It does so spontaneously and rapidly, leaving little room for correction later.

Some research suggests we make these decisions based on a person’s face in as little as 33 milliseconds.

A 2010 study by researchers at University College in London and Princeton University found the more a candidate’s face was perceived as showing familiarity or attractiveness, the more likely he or she would be voted into office.

“First impressions based on appearances are remarkably influential, frustratingly difficult to overcome, and occur with astonishing speed,” that study concluded.

Few voters, however, are likely to choose between Trump or Clinton based on first impressions because both have been in the limelight for the majority of their adult lives. This could play into favor for third-party candidates, like Jill Stein or Gary Johnson.

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Choosing image over substance has been fodder for political commentators for years, as they argue politics should be about picking the best candidate based on merit, not how they appear on a television screen.

Then again, it’s often difficult for people to disassociate these biases when entering the voting booth.

Such is the storied example of the 1960 presidential debate between then-Senator John F. Kennedy, and then-Vice President Richard Nixon.

Prior to Sept. 26, 1960, presidential debates were done over the radio, where nonverbal cues and appearances weren’t available for voters to judge.

During the first televised presidential debate, the power of appearances became abundantly clear.

Nixon was exhausted from campaigning and recovering from the flu, while the younger, tanner Kennedy had spent the weekend in a hotel resting for the event. Nixon’s grey suit blended in with the background, while Kennedy’s dark suit helped him stand out.

The election was decided by a razor-thin margin, and up to 6 percent of the voters said that seeing the debates alone determined their choice. Since then, a candidate’s media presence goes beyond official portraits and a smooth radio voice.

As Porter and Baker say, there’s something about a politician’s face that influences our decisions, even without our conscious consent.

“Individuals with faces that are representative of what we know from research to be ‘untrustworthy-looking’ would be harder to believe regardless of their honesty,” they said.