There are 250,000 to 500,000 people in the United States who are tax protesters, says JJ MacNab, a financial analyst who has written a book on the issue and testified before Congress on behalf of law enforcement.
Some, she says, are elderly, uneducated or disenfranchised people who buy into tax evasion scams. Others are disgruntled — sometimes dangerous — citizens who believe the wording of tax laws does not make them liable to pay.
"The tax laws are almost 100 years old, and no one has ever won," she says. "Thousands and thousands of people have challenged them. It's a constant flow of the same tired arguments over and over."
A summary of the case law on frivilous tax arguments from the IRS can be found here.