The United States was founded on the idea of independence. But what happens when a group of people declare independence from the U.S. itself?

“A sovereign citizen is an individual that believes the U.S. government does not have any legal jurisdiction over them,” said FBI Supervisory Special agent William Petoskey.

The FBI estimates there are approximately 300,000 sovereign citizens in the U.S. Over the years, the bureau has recovered a slew of illegitimate documents from members of the group — fake passports, a forged U.S. Marshal’s badge, even un-authorized license plates.

One sovereign, Lee Cromwell, of Anderson County, has made headlines in recent weeks, as his trial moves forward. Cromwell is accused of killing a man with his truck on July 4, 2015. By filing liens against county officials, the judge in Cromwell’s case was forced to recuse himself, delaying the proceedings.

Jim Scott, who represents Cromwell in court, said his client is a loyal Christian who frequently volunteers in the community. He said his client may identify as a sovereign citizen, but is “a real paradox between his actions and his ideologies.”

Though many who identify as sovereign citizens will never become violent, the FBI classifies them as domestic terrorists.

“But we also have that same individual out there who may take action that creates a violent situation,” said Petoskey. “So because those individuals are out there, we’re often concerned about where they are, what’s their grievance, and how they express that grievance. And, what actions they’ll take.”

The practice of filing fraudulent liens, often for millions of dollars, against government officials is a common sovereign tactic, according to the Southern Poverty Law Center, which calls it ‘paper terrorism.’

“I do think it a valid phrase in some cases,” said Petoskey. “ The sole purpose of terrorism in some cases is to stop you from doing your job using whatever means I can. That’s including harassing paperwork filed against you.”

In Knox County, 10News found a long list of elected officials with liens filed against them by sovereign citizens. Sorting it all out can take months to years for the target, even if the law catches up eventually.

“So their ability to deny jurisdiction of the Federal government is no different than you and I denying gravity,” said Petoskey. “It’s still there. And still conforms to those laws.”

Petoskey said he believes many people choose the sovereign life out of desperation or frustration. But he also warns that acting on some of those ideals can have consequences.

“If you’re going to violate the law, it will cause you trouble long term,” Petoskey said. “Be aware of it. Go into it eyes wide open.”