Hennepin County Attorney Mike Freeman announced second-degree assault and second-degree riot charges against one and second-degree riot charges against three others involved in a shooting at a Minneapolis protest, but stopped short of issuing hate crime charges. (Reuters)

Last year, when the National Consortium for the Study of Terrorism and Responses to Terrorism surveyed hundreds of law enforcement officials about what they believed to be the greatest terrorist threat in the U.S., the answer was not neo-Nazis or Islamic extremists.

It was “sovereign citizens,” a strange subculture united by little more than anti-government ideology and a sense of desperation. Adherents are said to include Terry Nichols, who helped plan the Oklahoma City bombings, and Jerad and Amanda Miller, who killed two police officers and a civilian who attempted to intervene in Las Vegas last year.

And, according to authorities, the philosophy also found a fan in 23-year-old Allen “Lance” Scarsella, the man charged with shooting five people at a Black Lives Matter demonstration in Minneapolis last week.

Scarsella and three other men, who prosecutors say were also armed, allegedly showed up at the demonstration last Monday intending to set off a confrontation with people protesting the fatal police shooting of Jamar Clark on Nov. 15. Scarsella fired eight shots, wounding five people. He and the three others are facing second degree riot charges.

[Four men charged after protesters shot near Minneapolis police protests]

Though the shooting is not currently being investigated as a hate crime — prosecutor Mike Freeman said that the sentences for riot and assault are heavier than a hate crime charge in Minnesota, though he would be open turning the case over to the Justice Department for federal hate crime charges — Freeman had no doubt that the crime was racially motivated.

“The defendants’ own statements, their videos, show that these are sick people,” he said in a statement. “Maybe I shouldn’t say that, but the language they use, and what they say about fellow Americans, citizens, are just not acceptable.”

VIDEO: Last night 2 white supremacists, one carrying a pistol, showed up to our peaceful protest at the 4th precinct.After community members on livestream started questioning them they left without incident, then we later found a video of them en route to the protest brandishing a pistol and making comments including “stay white” and justifying the killing of Jamar Clark.It has come to our attention that members of this group plan on returning tonight to our candlelight vigil at 4:30, some may come armed. [See: http://pastebin.com/FkA1B2rq]They say they will be wearing the “4 of clubs” to identify one another, so watch for this badge or patch on their clothing.In the era of white supremacist terrorism against people of color across the U.S., we refuse to be intimidated by hate groups. We call on our supporters to join us tonight to continue to demand #Justice4Jamar and an end to violence against our community, whether by white supremacist citizens, or white supremacist Police like MPD union president Bob Kroll.

Posted by Black Lives Matter Minneapolis on Friday, November 20, 2015

Editor’s Note: This video contains graphic language.

According to the criminal complaint, Scarsella, who is white, spoke derogatorily about African Americans and stored racist images on his cellphone. He allegedly filmed himself and another man (identified as J.T. in the complaint) headed to an earlier Black Lives Matter protest dressed in camouflage clothing and pledging to “make the fire rise” — an apparent reference to an anarchic character in the Batman movie “The Dark Knight Rises.”

And a Minnesota police officer who knows Scarsella described him as having “very intense” pro-Constitution and sovereign citizen views.

[The chilling video that foreshadowed violence days before Minneapolis shootings]

The “sovereign citizen” subculture is less a coherent movement than a loose philosophy, according to a report from the FBI’s Counterterrorism Analysis Section. People attracted to its ideas typically attend a seminar or view an online video, then make their own decisions about what to do with their newfound knowledge.

The basic tenets of the sovereign citizen ideology are complicated and wildly conspiratorial. They say that they aren’t American citizens but instead “non-resident aliens” not subject to taxes, government regulations or any local, state and federal laws. They deny the legitimacy of the Fourteenth Amendment, which in the wake of the Civil War guaranteed citizenship and civil rights to everyone born in the U.S. — an argument sovereign citizens have used to justify discrimination against African Americans.

They also believe that common law in the American legal system has been secretly subverted by a new system under which citizens are slaves. Their reasoning: When the dollar was taken off the gold standard in 1933, instead backed by the “full faith and credit of the U.S. government,” that meant that the government was putting citizens up as collateral. Documents like birth certificates and Social Security cards aren’t guarantees of identity but evidence that a corporate trust has been set up in that person’s name, allowing the government to restrict their rights and effectively enslave them. For that reason, many sovereign citizens carry false drivers licenses, prefer personal seals or fingerprints to signatures and alter their names with colons and other odd punctuation marks — distinguishing their true identities from the “straw man” accounts set up by the government.

Alfred Adask, a so-called “sovereign guru” who has been a sovereign citizen about three decades, told CBS in 2012 he believes “it’s un-American to trust the government.”

Adask said he does not collect Social Security benefits, even though he’s eligible, and owes back taxes to the IRS that he hasn’t paid.

“I think the government has gone far beyond its constitutional limits,” he said, adding that “one of the ways you prevent the misconstruction or abuse of the powers of the Constitution is by letting the people in Washington understand that you are armed.”

The interview was just after the 2011 Tuscon, Ariz., shooting that injured Rep. Gabrielle Giffords and killed six other people (the shooter, Jared Loughner, is said to have espoused beliefs similar to those of sovereign citizens).

“In this current atmosphere … some people might find your remarks troubling,” the reporter interviewing Adask said.

“Yeah, some people might. You know, I find it troubling that the government would try to restrict our right to keep and bear arms. The threat of violence is required because they will not listen. The system will not listen to people like me unless there are other people that back me up who have guns,” Adask said.

The Southern Poverty Law Center, which tracks hate groups, writes that the sovereign citizens movement is “rooted in racism and anti-Semitism.” Many sovereign citizens also believe that Jews have manipulated government and financial institutions to seize wealth and power.

Not all sovereign citizens subscribe to racist and anti-Semitic ideology — indeed, in the early 2000s a group of African American accused of drug dealing and other crimes in Baltimore federal court used sovereign citizen ideas to defend themselves against prosecution.

And though people citing sovereign citizen beliefs have been implicated in a whole swath of violent crimes — cop killings, arranging a hit on a federal judge, a plot to abduct, torture and kill police, an attempted armed assault on a Georgia courthouse — they’re much better known for what the Southern Poverty Law Center termed “paper terrorism.”

In dozens, even hundreds of cases across the country, sovereign citizens have filed frivolous lawsuits and legal claims on property called liens to intimidate or harass law enforcement officers. Many are financially desperate or fed up with bureaucracy, like a Minneapolis couple who filed nearly $250 billion in liens and other legal claims after they lost their home to foreclosure in 2009.

The couple, Thomas and Lisa Eilertson, learned the tactic from “P.K.” a man they met online, according to the Twin Cities Pioneer Press. He called it “death by a thousand paper cuts.”

Ramsey County Attorney John Choi called it “financial and economic terrorism.”

Elsewhere, adherents have been convicted of tax fraud, issuing false license plates and other documents, money laundering and debt evasion schemes.

2011 report by the FBI’s counterterrorism analysis section warned that the threat from sovereign citizens would likely grow, fueled by economic troubles and the Internet’s easy access to men like “P.K.” And when challenged, the most extreme adherents could become violent.

Such was the case with Jerry Kane, a father who along with his son got into a shootout with police officers during a traffic stop in West Memphis, Ark., in 2010. When asked for his license, Kane instead handed over a document declaring his sovereignty, according to CBS. An argument ensued, then a gun fight. By the time it was over, both Kanes were dead, as were two officers. Two more cops were injured.

“They’re willing to die for what they believe in,” West Memphis Police Chief Bob Paudert, whose son was one of the slain cops, told CBS. “These international terrorists that bombed the twin towers, they were willing to die for their beliefs. The sovereign citizens, the Kanes, are the exact same thing.”

It’s not clear how much, if it all, sovereign citizen ideology motivated Scarsella, the alleged Minneapolis shooter. The criminal complaint against him alleges he and the other three men left a digital trail of racist posts and plans for the shooting, including cellphone photos of them holding guns in front of a Confederate flag and racist images.

According to the Minneapolis Star Tribune, the four men charged on Monday got to know one another at school and through “/k/,” a  weapons-related message board “with racist overtones” on the website 4chan.

On the Facebook page that appears to belong to him, Scarsella doesn’t mention the sovereign citizen movement or its tenets. The profile is an odd mix of fringe affiliations and the kind of things you’d expect from any 23-year-old.

Scarsella’s “liked” pages include “Epic Vines” and the movie “Braveheart,” but also a pro-Second Amendment group whose profile picture is the numeral III surrounded by stars — a symbol of the anti-government “three percenter” movement. His profile picture shows him grinning toothily in the front seat of a car. But his cover photo is an image of the “Bonnie Blue Flag,” the unofficial Confederate banner at the start of the Civil War.

“This isn’t the somalian flag, btw” he commented on the image, making sure anyone who saw it knew where his affiliations lay.