Prosecutors say Kyle Rittenhouse, armed with a semi-automatic rifle, killed two people and injured one on the streets of Kenosha, Wisconsin, when he opened fire on Aug. 25 during protests over the police shooting of Jacob Blake.

Wisconsin law stipulates the minimum age for legal armed carry is 18. Though Rittenhouse is just 17, he stood that night with other armed civilians who declared they were out protecting property.

It remains unclear whether he was part of a formal militia group. In an interview with the conservative news website the Daily Caller earlier Aug. 25, the Illinois teen laid out the reasons he was in Kenosha. “So people are getting injured, and our job is to protect this business, and a part of my job is to also help people,” Rittenhouse said, without specifying any authority to do so. “If there’s somebody hurt, I’m running into harm’s way. That’s why I have my rifle because I need to protect myself, obviously. But I also have my med kit.”

Within hours, the patrolling turned deadly. Rittenhouse is now charged with two counts of first degree homicide and one count of attempted homicide.

His attorney told NBC News that Rittenhouse was exercising his right to defend the community.

“Kyle and all able-bodied males between the ages of 17 and 45 are part of the unorganized United States Militia,” John Pierce said in an email. “He was in Kenosha as part of his right and duty to protect his community where the state and local government had totally failed in their most basic responsibility to provide law and order.

“Specifically, he was there to protect the people and property of Kenosha from rioters bent on destroying it and burning it to the ground,” Pierce continued. “All United States citizens have this right and obligation where government fails. No American is too young to possess a rifle when state and local government refuses to protect them.”

Unorganized militias are not a new phenomenon, but have gained increasing attention and support over the last few decades. Modern militias and individual vigilantes appeared in the early 1990s positioning themselves as contrary to the federal government. After a period of relative quiescence, they re-emerged over the last decade in a more visible role not only in several high-profile protests, including Black Lives Matter, but also less known local disputes in towns around the country from Utah to New Mexico. These groups are self-anointed, weapon-bearing, so-called enforcers of order with very little stopping them, experts who study militias say.

“They consider themselves part and parcel of the enforcement regime,” said Robert Futrell, a professor who researches far-right extremism at the University of Nevada, Las Vegas. “They are self-appointed groups of local citizens who become law enforcement in their community. They may not have legal authority, but that does not matter because to them they have moral authority.

“But militia means military, and militia also means a capacity for violence.”

Two waves

In 2019, the Southern Poverty Law Center documented 181 active anti-government militias operating across the U.S. These groups cover a wide spectrum of ideologies but historically center around stopping the overreach of government.

The modern militia movement largely flowed in two waves, experts say. The first came in the early 1990s with anti-government standoffs like those in Ruby Ridge, Idaho and then in Waco, Texas – when the standoff between the Branch Davidians and the federal authorities turned deadly. A second wave occurred with the election of President Barack Obama, whom militia groups saw as a significant threat, particularly to their Second Amendment right to bear arms, according to Futrell.

But the election of Trump flipped the script, he said.

Some of these anti-government groups saw a sympathizer leading the country, prompting many members to shift their target to a new enemy in immigrants, Muslims, anti-fascist protesters and other “armies of the deep state,” including Black Lives Matter, he said.

Howard Graves, a senior research analyst for the Southern Poverty Law Center said “a major piece of the narrative that’s been circulated in anti-government militia circles since the killing of George Floyd has been the idea that Black Lives Matter is a ‘terrorist’ organization.”

“For the most part, militias have focused on the instances of looting and fires to advance the narrative that all BLM events are dangerous,” he added, “and modern militias have responded by trying to spin the narrative that it’s their constitutional duty to help local law enforcement and, therefore, their presence is needed in order to keep communities safe.”

Since the spring, militias have shown up at Black Lives Matter protests at least 55 times, according to the Southern Poverty Law Center.

One of the largest militia groups, the Oath Keepers, a group composed of thousands current and former law enforcement and military members, went to Ferguson, Missouri, in 2014 after the police killing of Michael Brown, 18, a Black teenager, and the ensuing protests. Members showed up armed and wearing camouflage gear, standing on rooftops to declare they were there to protect private property. Their presence, St. Louis County police Chief Jon Belmar told NBC News at the time, was “both unnecessary and inflammatory.” Police eventually ordered them off the rooftops.

The Oath Keepers did not return a request for comment by NBC News.

A different militia group was front and center in Charlottesville, Virginia, in 2017 during the Unite the Right rally that turned deadly when a far-right extremist drove his car into a crowd of counter-protesters, killing one and leaving 19 others injured.

“At that rally, the Light Foot Militia claimed it was helping to keep the peace, but members primarily acted as security for various right-wing extremist factions present that day,” Graves said.

Jeff Stankiewicz, founder of the Light Foot Militia who heads the Idaho branch, said in an email that he was not involved in Charlottesville and each branch is independently operated but that the faction that attended was trying to “maintain peace at what was supposed to be a rally in support of American history,” and “in no way had anything to do with any violence that occurred that day.”

Alex Friedfeld, an investigative researcher with the Anti-Defamation League, a civil rights watchdog group that tracks the far right, said militias often attend protests and rallies because “in their mind, they are trying to even the playing field.

“What animates these groups is anti-government, but it’s also anti-left,” he said. “Not only are they not trained and don’t have the same restraint as law enforcement, they also have their own agenda so they are more likely to clash.”

‘Fever pitch’

In Wisconsin, the Kenosha Guard, a self-identified local militia, set up an event on Facebook calling for people to take weapons into the streets and asked: “Any patriots willing to take up arms and defend [our] City tonight from the evil thugs? No doubt they are currently planning on the next part of the City to burn tonight!”

Kevin Mathewson, leader of the Kenosha Guard, wrote the post and told NBC News in an email: “Just like many other citizens of Kenosha, I watched businesses and homes burn to the ground 5 blocks from where my wife and I raised my two children. Our Mayor, County Executive, and Governor, all democrats, failed to keep us safe – filled with too much pride to ask for help. The police were extremely outnumbered. Our only option was to take up arms and defend our families and homes. The second amendment was written for this very circumstance.”

No one can say if Rittenhouse saw the original Facebook message, or is connected to the group, but the event received 300 RSVPs, with an additional 2,300 people interested in attending, according to a report by the Atlantic Council’s Digital Forensic Research Lab, which tracks online extremism. Facebook took down the Kenosha Guard page a day after the shootings, saying it was in violation of a new policy rolled out by the company to remove posts connected to violence.

“It’s a long-held fantasy of right-wing militia groups,” said Megan Squire, a computer science professor at Elon University who tracks online extremism. “They are inventing a scenario in which they can put their gun collections to use by showing up, unbidden, to ‘protect’ businesses that in many cases aren’t theirs and don’t want that service.”

“The online rhetoric among armed militias and other right-wing gun enthusiasts Is really at a fever pitch this whole summer,” Squire said. “Now, we’re seeing that come to bear in real life.”

Earlier this year, armed militias stormed statehouses in Michigan and Ohio to demand “freedom” from COVID-19 lockdowns.

For a long time, militia activity has largely been associated with a small fringe population, but in recent times, it is becoming more common to see militia groups forming and self-activating not only in high profile controversies but also in local conflicts. They have shown up to protect Confederate statues, detain migrants, and patrol high school students protesting racial injustice.

While most militias are constitutionalist and anti-government centered, there are also factions that commingle this ideology with white supremacy and neo-Nazism, according to the Southern Poverty Law Center. “It’s not that every militia member is white supremacist, they aren’t. But there is a lot of overlap with white supremacy and anti-government groups for a variety of reasons,” Futrell the University of Nevada professor, said. “In fact, a part of the re-emergence, that second wave, was charged by that ideological position.”

The ideology of many of these groups may not be outwardly associated with white supremacy, Mary McCord, a law professor at Georgetown University and legal director of the Institute for Constitutional Advocacy and Protection, agreed, but comments can be found from them online that are racist, xenophobic and disparaging of people of color and immigrants.

It may not be universal, but this trope appeared in comment threads made after the initial Facebook call to come to Kenosha.

When asked about the racist tone some comments took, Mathewson said, “As to the racist comments, neither I nor Facebook had the resources to remove any inflammatory comments. The page gained too much support too quickly to be moderated.”

A fundamental misunderstanding of the Second Amendment

All 50 states have some legal provisions prohibiting private militias from operating outside of governmental authority, but those statutes are largely unenforced, McCord said. That may be due to a fundamental misunderstanding of the Second Amendment, particularly in open carry states.

Many local officials, including law enforcement, don’t understand what is protected under the amendment, and they think these individuals are exercising constitutional rights, she said.

McCord said that in 2008, the Supreme Court ruled in District of Columbia v. Heller that the Second Amendment protects an individual’s right to bear arms for one’s self-protection, but the Second Amendment does not prevent states from prohibiting paramilitary organizations.

She said police and local officials should make it clear to militias, who often reach out to them before arriving, that not only do they not want their help, but also their help is illegal. They should also make it clear that they will enforce any laws that prohibit their actions.

Video surveillance analyzed by The New York Times showed that less than 20 minutes before Rittenhouse allegedly fired shots, police officers drove past him and the other armed civilians and offered water out of appreciation.

Police did not respond to a phone call and email request for comment by NBC News, but Kenosha County Sheriff David Beth told The Associated Press on Friday that the officer seen giving out water was not one of his deputies, and the person who said he appreciated what the armed civilians were doing “doesn’t mirror all of law enforcement’s perspective on what happened.”

Friedfeld, who has long studied militias, said that when police do not actively discourage militias and vigilantes, “there is almost this tacit condoning of this behavior.”

“Even if police aren’t singing their praises,” he said, “the lack of telling people to go home sends a message, and these guys are taking the message that they are allowed to be there.”