Time to revisit the ‘Klein’ conspiracy doctrine

Predicated on the 1957 decision by the U.S. Court of Appeals for the Second Circuit in United States v. Klein,1 federal tax indictments often include an allegation that the defendants conspired to "defraud the United States and the Internal Revenue Service by impeding, impairing, defeating and obstructing the lawful governmental functions of the IRS in the ascertainment, evaluation, assessment, and collection of income taxes." While some commentators have questioned the statutory authority for the so-called Klein conspiracy,2 given its extensive support in Supreme Court precedent and appellate case law, challenges to the charge have rarely gained traction.