Ben Terris is a writer in the Washington Post's Style section with a focus on national politics.

“I just want to make sure,” my editor asked me as he closed the door to his office. “He definitely grabbed her?”

It had to be the 50th time I’d heard this question, and each time it filled me with unspeakable anxiety.

Yes, he grabbed her. It happened three days earlier, in the chandelier-lit ballroom of Donald Trump’s golf club in Jupiter, Fla. Trump had just won the state’s primary, and he was celebrating in a ballroom full of Trump-branded products: steaks, water, even a magazine.

After the speech, Michelle Fields, a reporter for Breitbart, approached Trump with a question about affirmative action, when Corey Lewandowski, then Trump’s campaign manager, took her by the arm and yanked her from the candidate.

It happened right in front of me.

And yet, even though I saw it, the Trump team’s response — to claim it never happened at all — would become a small preview of a strategy the campaign would return to again and again on a much larger scale this year: Bully, don’t back down, do whatever you can to muddy up the facts. It was a type of lie that has lived at the center of the Trump campaign. This was not simply a misreading of history, an embellishment of biography, or a dishonest interpretation of a piece of legislation. It was a flat-out denial of something that undeniably happened.

The Jupiter, Fla. police department released a video that appears to show Donald Trump's campaign manager, Corey Lewandowski, grabbing Breitbart reporter Michelle Fields. Lewandowski was charged with battery by police on March 29. (Jupiter Police Department)

Later in the year, Trump would employ these same tactics to deal with a flurry of crises, most recently to combat numerous accusations of sexual misconduct. By most accounts, Trump lies at a rate much higher than Hillary Clinton, but he does it with such confidence that he’s still seen as more trustworthy than his opponent. From an outside vantage point, it can be difficult to tell fact from fiction. From the inside, it’s even more disorienting.

After I left the primary night event in Jupiter, the story about Lewandowski leaked out on Twitter before I wrote it. Once it was out there, the campaign set about on a coordinated effort to discredit Fields and me. Lewandowski called Fields “delusional” and said he “never even met [her].” Surrogates pointed to Zapruder-like footage that they said exonerated the campaign manager, and aides issued a statement that claimed “not a single reporter” saw the incident.

In the moment, I was sure it happened. I asked Fields if she was okay. (She was bruised and a bit rattled.) I told her it was Lewandowski who had grabbed her. There was no question.

But by the time my editor asked me about it three days later, doubt had started to creep in. Trump had suggested Fields was probably making it up, and nobody else had corroborated my account. If it had really happened, Trump and his surrogates maintained, why wasn’t there any footage?

* * *

Of course the 2016 election, this psychological battlefield of a campaign, would introduce “gaslighting” into the political lexicon. Until recently, the term has been reserved mostly for a form of domestic abuse wherein one partner, through lies and charm, persuades another that the things she’s seen and heard simply did not happen.

Reporters and political junkies experienced this in a collective way during the vice-presidential debate in October, when Gov. Mike Pence (R-Ind.), Trump’s running mate, shook his head “no” to the charge that Trump had praised Vladimir Putin. He denied that Trump had suggested more nations get nuclear weapons, that Trump had proposed a “deportation force” to go after undocumented immigrants, and that Trump wanted to punish women for having abortions.

Never mind that the political press, along with many others, had watched the Republican nominee say all these things in the preceding weeks and months, and it was all on tape. Trump’s running mate used “polish and confidence,” wrote Jamelle Bouie in Slate, “to deny Trump’s rhetoric and behavior and gaslight the country that has borne witness to them.”

Gaslighting can be frighteningly effective, especially on a person who has a realistic sense of humility about perception and memory. Reporters are trained to apply skepticism to sources who rely on their memories; when you’re the source, this skepticism can turn inward.

I know, because on a very small scale, it happened to me.

In the days after the grabbing incident, I started reading articles about the science behind false witness accounts. (Did you know that in 2012 researchers found that there were more than 2,000 false convictions over the past 23 years? Can you guess the number one reason?) After I wrote up my version of what happened, Joel Pollak, one of Fields’s colleagues at Breitbart, published a “Loose Change”-style analysis of several videos and still photographs purporting to prove the events“could not possibly have happened as Ben Terris reported.”

As the story plowed through multiple news cycles, people kept asking me if I was 100 percent sure I saw it happen. I had my memory, and I had a record of my conversation with Fields after the incident. Still, absolute certainty is an uncomfortable feeling for a journalist. It should be hard to say something definitely happened, just as it should be hard to say something “could not possibly have happened.”

I turned down dozens of television interviews on the subject. I worried I might say something like: “No, I’m not 100 percent certain of my account because I’ve never been 100 percent certain about anything.” And then I’d find a Breitbart headline like: “WaPo reporter no longer sure he saw what he said he saw.”

A few days later, video from Trump’s own security cameras finally surfaced that clearly showed Lewandowski grabbing Fields by the arm and yanking her away from Trump.

The Jupiter, Fla. police department released a video that appears to show Donald Trump's campaign manager, Corey Lewandowski, grabbing Breitbart reporter Michelle Fields. Lewandowski was charged with battery by police on March 29. (Jupiter Police Department)

I thought that would put the issue to rest, but I was wrong. The video demonstrated that Lewandoski and his allies had lied about what happened, but Trump supporters used the same video to “prove” that Lewandowski was vindicated. “He barely touched her” became a common refrain.

In a sense, the Trump campaign played it brilliantly, intentionally or not. First they asked why, if Fields had really been grabbed, she didn’t go to the police. When she called that bluff and filed a report, they then painted her as having overreacted to a relatively minor altercation.

(Fittingly enough, it turned out nothing in that Florida ballroom was what it seemed: The glossies weren’t really Trump Magazine, but a glorified pamphlet handed out to visitors at various Trump properties. The Trump water was bottled by another company. The Trump steaks were replicas of a product Trump once sold and doesn’t anymore; the campaign hadn’t even bothered to remove the wrapping from the real company, Bush Brothers, that had provided them.)

Meanwhile, Trump’s aides just kept trying out different excuses. At one point, they said Lewandowski was simply protecting his boss from Fields, who they claimed was coming at him with an unknown object, perhaps “a little bomb.”

It was a pen.

* * *

All this happened back in March. It was still primary season, and the real estate mogul was in the process of transforming from spoiler to standard-bearer. His campaign was aggressive, but mainly in its rhetorical posturing. Most journalists had not yet started to focus on the women Trump himself might have grabbed, nor by what part of the anatomy.

But today, Trump’s form of crisis management feels particularly familiar. When numerous women accused Trump of sexual harassment this fall, he said that he had never even met them (no matter that one of them profiled him for People magazine and another had been on “The Apprentice” with him). Trump encouraged voters to “check out” the sex tape of Alicia Machado, the former Miss Universe who accused him of calling her “Miss Piggy,” even though no such tape appeared to exist. And one of Trump’s spokeswomen said it was impossible for him to have groped another woman on an airplane because armrests didn’t move up and down at the time (which proved to be not only ridiculous, but also untrue).

The Trump campaign has told many lies since Lewandowski lied about grabbing Fields in that Florida ballroom. Trump lied in front of millions by claiming that Hillary Clinton’s campaign started rumors that President Obama was foreign-born (it didn’t). He lied when he said he started his business with a “very small loan” from his father (which is only true if you consider $14 million a small loan). Professional fact-checkers have checked hundreds of Trump’s statements and judged him to be less truthful than any presidential candidate they have seen. And yet, he’s got an ability to come across as a truth-teller, at least to his supporters: 87 percent of Republicans see him as more honest and trustworthy than Clinton.

When I spoke with Fields last week, she told me that at the time even she began questioning her own account, despite having the bruises to prove it.

“The Trump campaign did everything they could to get me to question my own reality,” she said. “You don’t think that will ever happen to you, but it did.”

It’s been a hard few months for Fields. She lost her job at Breitbart, and though she now works for the Huffington Post, she admits she’s begun questioning the power of the press. She had her phone number and apartment address posted online and received death threats. And watching Trump battle with his recent female accusers has only made things worse.

“It broke my heart,” Fields said when I met up with her recently. “He was attacking these women, and I remember thinking that I knew what they felt like: completely powerless. You know the truth, and you are watching this person lie to millions of people, and what can you do?”

What worries Fields is that if Trump can get people to second-guess their own experiences, imagine how effective he can be convincing people who weren’t even there. It’s the kind of power that can get someone elected president.

“Trump gaslighted me,” Fields said. “I worry now that he’s gaslighting the country.”

Read more:

This is the speech Trump could give if he loses the election but refuses to concede

Trump is wrong. Rigging an election is nearly impossible.