The National Association of Secretaries of State released a report in April on sovereign citizens, urging state officials to find ways to expedite the removal of liens and increase penalties for fraudulent filings. More than a dozen states have enacted laws giving state filing offices more discretion in accepting liens, and an increasing number of states have passed or are considering legislation to toughen the penalties for bogus filings.

The Eilertsons, who were charged with 47 counts of fraudulent filing and sentenced in June to 23 months in prison, were prosecuted under a Minnesota law that makes it a felony to file fraudulent documents to retaliate against officials. John Ristad, an assistant Ramsey County attorney who handled the case, said he believed the Eilertsons were the first offenders to be prosecuted under the law. “It got me angry,” he said, “because at the end of the day, these two are bullies who think they can get their way by filing paper.”

The liens were filed against houses, vehicles and even mineral rights. In an affidavit, the Hennepin County examiner of titles said that in a conversation with the Eilertsons about their foreclosure, one of them told her, “We’re gonna have to lien ya.” The examiner later found that a lien for more than $5.1 million had been placed on her property.

If the purpose was to instill trepidation, it worked. Several county and state officials said in interviews that they worried that they might once again find themselves in the crosshairs. One state employee said it was scarier to engage with offenders who used sovereign citizen tactics than with murderers, given the prospect of facing lawsuits or fouled credit ratings.

Like many who identify with the ideology, the Eilertsons learned the techniques of document filing online from one of many sovereign citizen “gurus” who offer instruction or seminars around the country.

In hours of recorded conversation found by the authorities on their computer, the Eilertsons consulted with a man identified on the recordings as Paul Kappel, learning what he called “death by a thousand paper cuts.”

Mr. Eilertson, interviewed at the state prison in Bayport, Minn., denied being anti-government or belonging to any movement. But he was familiar with the names of some figures associated with sovereign citizen teachings, including an activist named David Wynn Miller, who Mr. Eilertson said was “ahead of his time.” (Mr. Miller writes his name as David-Wynn: Miller.)