Tax evasion in the United States unlawful gains as income when filing annual tax returns (see e.g., "James v. United States") although such income is typically not reported. Suspected lawbreakers, most famously Al Capone, have been successfully prosecuted for tax evasion when there was insufficient evidence to try them for their non-tax related crimes. Reporting illegal income as earned legitimately may be illegal money laundering. In the United States, the IRS estimate of the 2001 tax gap was $345 billion. For 2006, the tax gap is estimated to be $450 billion. A more recent study estimates the 2008 tax gap in the range of $450 to
Tax evasion in the United States show (1) the existence of a tax deficiency (an unpaid federal tax), (2) an affirmative act constituting an evasion or attempted evasion of either the assessment or payment of that tax, and (3) willfulness (connoting the voluntary, intentional violation of a known legal duty). A genuine, good faith belief that one is not violating the Federal tax law based on a misunderstanding caused by the complexity of the tax law is a defense to a charge of "willfulness", even though that belief is irrational or unreasonable. A belief that the Federal income tax is invalid or unconstitutional is not a