Criminal defense attorneys occasionally seek to have an indictment for perjury dismissed by raising the defense of "perjury trap."1 A perjury trap is set when a prosecutor brings a defendant before the grand jury in order to secure a perjury indictment, rather than to indict the defendant for a previously committed crime.2 There are numerous cases in which the perjury-trap defense has been asserted.3 But there are no federal cases granting a motion to dismiss because of a perjury trap.4 Defense counsel should never raise the perjury-trap defense. This Note will explain why.
Part II of this Note lays out the perjury-trap defense as defined by courts and commentators. Parts III and IV analyze the two general arguments that underlie the perjury-trap defense: a violation of the Due Process Clause of the Fifth Amendment and entrapment.5 Part V shows that immaterial testimony is a necessary element of the perjury trap. It also shows that immaterial testimony does not constitute perjury, making the perjury-trap defense superfluous. Part VI explains that federal courts construe the scope of materiality so broadly that defendants rarely succeed when arguing that grand-jury testimony is immaterial.
II. Perjury Trap
If a defendant believes that the prosecutor's primary purpose for bringing him before the grand jury was to procure a perjury indictment, he may raise a perjury-trap defense.6 The crux of the perjury-trap defense is that the prosecutor asked questions that were not material to the investigation,7 leading to the conclusion that the grand jury was used as a "ruse to manufacture a crime where none previously existed."8 In his article The "Perjury Trap, " Bennett L. Gershman states that in such instances, "the government's conduct in baiting the witness into perjury is a perversion of the grand jury's function and should not be permitted."9
To demonstrate the typical perjury-trap defense, it is instructive to recount the facts of a federal case involving an alleged perjury trap. In United States v. Chen,10 the federal government was investigating corruption within the Public Utility Agency of Guam (the Agency).11 During this investigation, two Agency employees revealed that they had received kickbacks from the defendant, Chen.12 The prosecutor eventually brought Chen before the grand jury, where Chen testified that he never made any payoffs to Agency employees.13 Chen was charged with giving false testimony before the grand jury under 18 U.S.C. § 1623. 14
On appeal, Chen argued that the testimony that formed the basis of his perjury indictment concerned alleged bribes on which the statute of limitations had already run.15 And, as a result, he contended the questions asked by the prosecutor in connection with the alleged bribes were not material to the Agency investigation.16 The court also responded to Chen's assertion that the prosecutor asked immaterial questions before the grand jury with the primary purpose of obtaining false testimony to be used in a perjury indictment.17 According to the court, such conduct would constitute a perjury trap, which might be a violation of the Fifth Amendment Due Process Clause as well as an abuse of the grand jury proceedings.18
The court of appeals held that while a perjury trap was theoretically possible, its elements were not satisfied in Chen's case.19 Before the grand jury, Chen denied committing bribery, and the statute of limitations on that bribery charge had run.20 But the scope of the prosecutor's investigation was much broader than just the activities of Chen.21 The court reasoned that an inference could have easily been made that Chen's payment of bribes extended beyond the two individuals who testified against him and that his testimony affected their credibility.22 Chen's lack of cooperation thwarted the grand jury's goal of flushing out all the possible corruption in the Agency, not just corruption directly involving Chen. …