COLUMBUS, Ohio -- They call themselves sovereign citizens, U.S. residents who declare themselves above state and federal laws. Many don't register children's births, carry driver's licenses or recognize the court system.

Some peddle schemes that use fictional legal loopholes to eliminate debt and avoid foreclosures. A few such believers are violent: Two police officers in Arkansas died in a shootout in May after stopping an Ohio sovereign citizen and his son.

As many as 300,000 people identify as sovereign citizens, the Southern Poverty Law Center found in a study to be published today that was obtained by The Associated Press. Hate group monitors say their numbers have increased thanks to the recession, the foreclosure crisis, the growth of the Internet and the election of Barack Obama in 2008.

Adherents expect the current American system of government to end one way or another. "I'm the Patrick Henry of the 21st century. I'm here to regain our freedom," James McBride said in a jailhouse interview. "I'm going to, or die trying."

At the heart of their belief system: The government creates a secret identity for each citizen at birth, a "straw man," that controls an account at the U.S. Treasury used as collateral for foreign debt. File enough documents at the right offices, and the money in those accounts can be used to pay off debt or make purchases worth thousands of dollars.

The movement is based on a form of "legal fundamentalism," said Michael Barkun, a retired Syracuse University political science professor who researches anti-government and hate groups.

"These people really seem to feel that filing certain kinds of legal papers that are connected to their theories will somehow also magically have the power to alter relationships and grant things that otherwise would be unobtainable," he said.

The sovereign citizen movement has grown to about 100,000 hard-core believers, the SPLC report estimates, and 200,000 people trying out the theories by "resisting everything from speeding tickets to drug charges."

In May, Jerry Kane, who pitched so-called redemption schemes for reducing debt, died in a shootout with West Memphis, Ark., police after authorities said his 16-year-old son, Joe, fatally shot two officers during a traffic stop.

Kane's Florida widow, Donna Lee Wray, denies her husband and stepson were sovereign citizens. She maintains a website that asserts they weren't involved in the officers' deaths.

McBride, the jailed sovereign citizen, came across anti- government beliefs while in federal prison in Michigan on a 1992 cocaine-importing conviction.

Over the years he developed his own tenets, including a revised history of the United States that says the country was secretly organized as a general post office in 1789. Today, McBride is headed back to federal prison after prosecutors said he cashed bogus checks and refused to cooperate with his parole officers following a 2004 bankruptcy fraud conviction.