Not so long ago, it was possible to laugh off the American militia movement as a bunch of old white guys and gun nuts playing army in the woods or freaking out about black helicopters. After the past five years, no one’s laughing: from the Bunkerville standoff to Unite the Right, armed right wing extremists have organized to put on their most brazen displays since the days of the Oklahoma City bombing.

This year, the Patriot Prayer events have sparked regular brawls in the typically calm streets of Portland, Oregon. In April, the xenophobic vigilantes in the United Constitutional Patriots broadcast themselves on YouTube rounding up hundreds of people crossing the border into New Mexico. At a special session of the Virginia Legislature convened in July to address gun violence after the Virginia Beach shooting, militia members stood armed along the route members of the public took to talk to their elected officials.

The rise in paramilitary activity could reach a fever pitch in 2020, since many anti-government groups have embraced President Donald Trump as their champion. For months, Trump has insinuated that any outcome short of his reelection should be considered illegitimate. Impeachment and the ongoing campaign could bring his most vehement supporters into the streets—armed.

Already, the Oath Keepers, a national network of armed far-right extremists, has volunteered to provide “security” at a number of Trump campaign events. The week of Thanksgiving, the group invited members of militias and biker gangs to come to a Trump rally in Florida, specifically encouraging volunteers with concealed weapons permits. The group’s leader, a man named Stewart Rhodes, has promised that impeachment will spark a shooting war. Meanwhile, on certain corners of social media, talk percolates of the “#boogaloo,” shorthand for violent resistance to Democratic presidential candidates’ promised gun control.

One might wonder if the country necessarily has to abide armed bands on its streets. In fact, the federal government and all 50 states have statutes or constitutional provisions that could be used to muzzle paramilitaries. Yet, the laws are rarely used.

One might wonder if the country necessarily has to abide armed bands on its streets.

Though they vary across the states, the anti–private army laws target the same basic phenomenon: forming armed groups not answerable to civil authorities, providing paramilitary training for use in civil disorders, and falsely assuming police or military roles. The constitutional provisions and statutes can form the basis for injunctions prohibiting members associating together while armed or setting up training camps, restrictions on public events like rallies, and even criminal prosecutions.

In one rare instance, Charlottesville used Virginia laws prohibiting private paramilitaries, false assumption of police duties, and more general public nuisances to sue a number of militias that attended the Unite the Right rally in 2017. That lawsuit resulted in a settlement banning members from returning to the city while armed in groups larger than two. Georgetown University Law School professor Mary McCord, who advised Charlottesville in its lawsuit, has since traveled the country, reaching out to other cities and states facing their own paramilitary problem.

While many of the relevant laws have criminal provisions, McCord often advises governments and prosecutors to send cease-and-desist letters, then pursue injunctions. As she describes it, the injunctions are sort of like “red flag” laws for paramilitaries: They can be used to preempt or regulate threatening behavior rather than wait for an outburst of violence. They are agnostic on ideological motivation or political purpose, unlike the domestic terrorism laws some have proposed. And they don’t impinge on First Amendment rights to free association, since they target conduct by organized groups that aim to intimidate or assume police duties, not protected speech. Nor do they run afoul of the Second Amendment, which has not been extended to private armies.

The response has been mixed, McCord told Slate. Some places have taken her advice. She consulted with Dahlonega, Georgia, on the best way to stop white supremacists bringing loaded weapons to a pro-Trump rally this September. The laws provided the justification for the temporary gun restrictions even though Georgia state law preempts typically cities from regulating where citizens can carry weapons. But when she tried to contact the New Mexico attorney general’s office after the United Constitutional Patriots fiasco, she never got a response. The federal government ultimately criminally charged one UCP leader for impersonating the Border Patrol, but the larger group just relocated its activities. In an emailed statement, the New Mexico attorney general’s office said that while it did not pursue enforcement using the state’s paramilitary laws, staff used McCord’s research when requesting funding for an anti–domestic terrorism unit.

McCord believes the problem is twofold: On one level, the laws and constitutional provisions are obscure, and authorities may not even know what tools they have at their disposal. They may be apprehensive about how such a legal strategy will fare in court, due to the paucity of precedent. But on another level, “it’s a matter of political will,” McCord said. Especially in red states, “there’s a lot of pressure not to do anything that could be perceived as an attack on gun rights.”

The laws specifically target paramilitary groups, but some caution that they aren’t a panacea for white supremacist or far-right violence. The “leaderless resistance” model embraced by extreme-right mass shooters seen in Charleston, South Carolina, and Pittsburgh — whereby networks of extremists share propaganda and tactics but act on their own — may pose the more acute violent threat. “The paramilitary aspect is not what concerns me. It’s the extremist aspect that concerns me. You don’t need any paramilitary training whatsoever to conduct terror attacks,” said Mark Pitcavage, a longtime expert on hate groups and the far right with the Anti-Defamation League.

But some straddle the paramilitary and terror cell line, like the Atomwaffen Division, a neo-Nazi group implicated in five murders. “They’re an accelerationist group. They talk about race war. They’ve produced videos of themselves training,” said Pitcavage. It seems clear that such a group is engaged in paramilitary training to foment disorder rather than just conducting target practice. The anti-private army laws could break up the organization in a way that murder investigations focused on particular perpetrators might not.

The escalating political tension ahead of the 2020 election intensifies the need to find a solution. “We have been seeing an increase in not just hate crimes, but political homicide and threats against politicians,” said Brian Levin, a law professor at California State University–San Bernardino and co-author of The Limits of Dissent: The Constitutional Status of Armed Civilian Militias. “In the climate of catalytic political events like elections or impeachment, we have a set of statutes that we can employ if we see escalated civil disorder.”

This January could provide a rare high-profile test for McCord’s strategy. That’s when the Virginia Legislature will reconvene with Democrats in control for the first time in more than 20 years. They have a mandate from Gov. Ralph Northam to reconsider the aggressive slate of gun control measures that the old Republican majority punted back in the summer special session. The gun control push is sure to provoke a response from the same armed militias who took it upon themselves to patrol other members of the public at the brief session in July.

But this time, Virginia Attorney General Mark Herring has suggested the state won’t tolerate another show of force from the paramilitaries. In August, after consulting with McCord, he issued an advisory opinion laying out the legal basis for taking action. The memo sets the stage for the first potential crackdown on the emboldened paramilitary right in 2020. Other states are sure to be watching closely.