'Replacement theory' fuels extremists and shooters. Now a top Border Patrol agent is spreading it.

Last month, Brandon Judd, who is a Border Patrol agent and the president of the National Border Patrol Council union that represents more than 18,000 agents, sat for an interview with Fox News anchor Bill Hemmer.

Wearing a black polo shirt bearing the crest of his union, the shaven-headed Judd stared intently into the camera as Hemmer asked him why he thinks President Joe Biden has allowed “virtually an open border.”

With a shake of his head, Judd responded, "I believe that they're trying to change the demographics of the electorate; that's what I believe they’re doing." As he spoke, the split-screen broadcast zoomed in on footage of people of color crossing the U.S.-Mexico border, and Judd continued, "They want to stay in power, and the only way to stay in power is to continue to stay elected."

Judd’s claim the Biden administration is actively working to weaken the nation’s southern border to allow in more immigrants and “change the demographics” of the nation is hardly new. The conspiracy theory that white Americans are being systematically “replaced” by immigrants from majority nonwhite countries has been a trope of American white supremacists and other racist extremists for decades.

The theory has been cited as inspiration for numerous race-driven mass shootings in recent years. According to extremism researchers, an 18-year-old man who killed 10 people and wounded three more in a shooting at a supermarket in Buffalo, New York, on Saturday previously posted a manifesto online that repeatedly references replacement theory as the reason for the shooting.

Law enforcement officials were working Sunday to confirm the validity of the manifesto and that it was posted by the alleged shooter.

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Immigrants including Hispanics are helping change demographics of the United States – indeed, based on census projections, many experts predict white Americans will be a minority as soon as two decades from now.

But the "Great Replacement Theory," pushed by hate groups across the world since the early 20th Century, claims this is not simply because of immigration, but is done by political design.

In its most extreme form the theory claims a cabal of powerful politicians, aided by sinister Jewish power-brokers, is deliberately working to replace white Europeans and Americans with nonwhite immigrants who are more likely to support left-leaning politicians. Though Judd did not provide this kind of elaborate story, he and others have promoted a portion of it.

In the past few years, the theory has been increasingly embraced by conservative pundits. Fox News' Tucker Carlson frequently invokes the theory, for example saying last April that "the Democratic Party is trying to replace the current electorate, the voters now casting ballots, with new people, more obedient voters from the Third World."

In 2018, pundit Laura Ingraham infamously said: "The America that we know and love doesn't exist anymore. Massive demographic changes have been foisted upon the American people, and they're changes that none of us ever voted for and most of us don't like."

So, when Judd turned up on Hemmer's America's Newsroom on a Monday evening, his rhetoric might have sounded familiar. But there was a key difference.

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Ingraham, Carlson and others are political commentators. Judd, by contrast is a federal employee, paid by taxpayers and tasked with the sensitive job of helping to police the nation's border for an arm of the executive branch of government.

That has experts on extremism concerned.

“This kind of rhetoric gives people the idea that they’re justified in being angry at people who they think are taking something away from them, or ruining their country," said Marilyn Mayo, a senior research fellow at the Anti-Defamation League’s Center on Extremism. "It can lead to people demonizing those folks or dehumanizing those folks.”

Judd refused to be interviewed for this story. But in a series of lengthy text messages to USA TODAY, he said he has never heard of the Great Replacement Theory, and that he learned of the concept of “changing the demographics” from a 2008 Politico article that outlined the changing racial makeup of the nation's voters.

Pressed on what he meant by “change the demographics," Judd wrote of illegal immigrants: “I do not KNOW that they are liberal voters, but generally speaking ILLEGAL immigration is not frowned upon near as much by liberals and these people violated" U.S. immigration laws.

He did not provide any evidence to back his claim that this demographic shift is specifically being engineered by the president and the Democratic Party.

A white supremacist theory goes mainstream

Political scientists have been predicting a significant shift in the way Americans vote because of changing demographics for more than a decade.

A 2020 Pew Research Center study concluded that "in all 50 states, the share of non-Hispanic White eligible voters declined between 2000 and 2018." At the same time, the researchers noted, "Hispanic voters have come to make up increasingly larger shares of the electorate in every state."

This growth primarily stemmed from the U.S.-born Hispanic population coming of age, the study noted.

For conservatives, this shift is concerning simply because nonwhite voters are historically more likely to vote Democrat than Republican. The changing demographics of the country, and the resulting impact on voting, then, is fairly uncontroversial.

But on Fox News, Judd didn't simply describe that the demographics of the country were changing. He claimed this change was being orchestrated by the Biden administration. And that's where a simple description of a changing electorate begins to sound similar to a white supremacist conspiracy theory.

On any given day, dozens, if not hundreds, of racists from around the world discuss the idea that white people are being “replaced” on sites like Stormfront, a white supremacist message board and on the secure messaging app Telegram.

“Never forget the Democrat Party is the party promoting The Great Replacement,” reads one anonymous post from last month on Stormfront. “There are no brakes on the anti-white train.”

The Great Replacement Theory has become one of the central tropes of white supremacist forums and publications, said Jared Holt a fellow at the Atlantic Council's Digital Forensic Research Lab who researches extremism.

"Great Replacement Theory is one of the cornerstones of white supremacist propaganda," Holt said. "Conservative media has figured out how to give a nod to the Great Replacement Theory without using some of the more explicit language that you might see on a forum like Stormfront or on sites like the Daily Stormer by talking about 'Changing demographics.'"

Wherever people learn about the theory, its general premises are absurd, said Allen Orr, president of the American Immigration Lawyers Association.

"Even if people are allowed in, they are so many years from being able to vote it is silly to even talk about it," Orr said. Besides, he said, "in some areas, particularly in Florida, large numbers of Hispanic voters vote Republican, so the idea that immigrants only vote for one party is ridiculous."

Whether or not a Border Patrol agent is promoting ideas that also appear on extremist sites, Great Replacement Theory is also repeatedly found in an even more dangerous part of the internet.

A theory inspiring terrorists

Before Brenton Tarrant murdered 51 people at two mosques in Auckland, New Zealand, in 2018, he published a manifesto online titled “The Great Replacement.” Tarrant described Muslim immigrants to New Zealand as "invaders."

A year later, when Patrick Crusius shot and killed 23 people at an El Paso, Texas, Walmart, he also penned a manifesto alleging a ”Hispanic invasion,” and referencing the Great Replacement. The theory was also alluded to by Robert Bowers, who killed 11 people at the Tree of Life synagogue in Pittsburgh in 2018 and by John Earnest, who killed one person at a synagogue in Poway, California, in 2019.

The bloodshed associated with this theory should make anybody think twice before echoing it, Holt said.

“Somebody like Judd can go on Fox News and regurgitate a line like this and the audience doesn't blink,” Holt said. “With all of the horror and hate that it's inspired over the years, they really should have some sensitivity. There's a context to rhetoric like that that should give people pause.”

Pedro Rios, a human rights advocate who works with several border-focused groups, said it is also especially troubling that somebody who speaks for, and is highly influential among, Border Patrol agents, is giving voice to this sort of rhetoric.

"This provides political cover, for the agents on the ground that that Mr. Judd represents, to also espouse these white supremacist ideas and theories that then might drive how they conduct their work, and how they behave when they are detaining migrants," Rios said. That could lead to "much more violence, much more mistreatment and abusive practices by the Border Patrol."

Making claims about government, while working for it

Slightly watered-down versions of the Great Replacement Theory have been increasingly spread by far-right-wing pundits. Unlike commentators, however, Judd has another full-time job: as a Border Patrol agent.

At the same time he is accusing Biden of being the “best friend” of Mexican drug cartels and claiming the president is encouraging illegal immigration to politically benefit the Democratic Party, Judd has also been paid by the federal government.

A spokesman for Customs and Border Protection would not answer specific questions about Judd’s Fox News appearances and articles, instead sending USA TODAY a statement:

“Federal employees have certain rights when expressing their personal views on matters of public concern. This individual is not a spokesperson for CBP. His comments were not made on behalf of the Agency nor do they represent our values.”

Requests for comment to the Department of Homeland Security, which oversees CBP, were not responded to.

Ethics experts and former federal officials expressed concern at Judd’s comments and questioned whether they might run afoul of the Hatch Act, which bars federal civil servants from engaging in overt political activity.

“That seems to be a conflict of interest,” said Javed Ali, associate professor of practice at the Gerald R. Ford School of Public Policy at the University of Michigan and a former senior counterterrorism official at DHS. ”You're not supposed to be crossing over into the political policy world when you're on the the federal taxpayer’s dime.”

Every American has a right to freedom of speech, as enshrined in the First Amendment. But there are many instances where that right is not absolute. One is police officers, who do not have an absolute right to say or do things that reflect badly on their departments.

David Lapan, a former spokesman for DHS, said Judd’s statements and articles were “highly unusual.” Customs and Border Protection is part of the federal law enforcement apparatus, Lapan said, which is traditionally seen as nonpartisan.

“Their job is to enforce, much like the military,” he said. “You serve at the pleasure of whomever the president is, regardless of party. You aren't partisan, because your job involves enforcing the law, regardless of who has the majority in Congress.”

This article originally appeared on USA TODAY: Replacement theory: Border Patrol agent spreads racist, extremist idea