The Austin man, accused of plotting a mass shooting by an FBI informant, may have ties to the group, sovereign citizens.

In Steven Boehle's arrest warrant, the same confidential informant claims Boehle "exhibits sovereign citizen extremism ideology."

The group's criminal elements have been tracked by Austin police for years.

Austin police commander, Darryl Jamail, said they have seen an increase of sovereign citizens and cases involving them. For police, dealing with people who don't believe in the government can be dangerous.

"In these types of situations, it gives it another layer of unpredictability, which raises the officer's concern for how this situation is going to turn out," said Jamail.

Commander Jamail is over the Austin Regional Intelligence Center. He said they only track people who break laws. Not groups, like sovereign citizens that haven't, despite what many believe.

Police said like with any organization, there are extremists. That makes the radicals within the group domestic terrorists. There are subgroups with the sovereign citizens.

"Some groups don't believe they should pay any form of taxes or recognize any government authority. They don't have state-issued license plates on their cars, they may not have their car inspected or have a drivers license," said Commander Jamail. 

Meantime, over at Brave New Books on Guadalupe Street, owner John Bush is skeptical about the investigation into Boehle. Bush said he does not know Boehle.

"This is yet another example of the FBI furthering their narrative that people that object to the federal government's authority are extremists and should be considered crazy and weird," said Bush.

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Every Sunday at Brave New Books, there's a traffic seminar for those who don't believe in driver's licenses and car registrations.

"People driving around without tags wanting to be left alone from a government institution that they don't believe in is not extreme," said Bush. 

Bush said he's part of a growing population that doesn't trust the government, calling the government illegitimate. He said he will only follow laws that are ethical.

And while Bush seeks sovereignty in everything he does, he doesn't identify with the group, sovereign citizens. Many he considers friends.

"And everyone that I know that's been a sovereign citizen is the most peaceful person you can imagine," said Bush.

Bush said more and more people are accepting his anti-government views. In fact, when he closes Brave New Books on the Drag at the end of April, he will open up three new locations.