conviction arose from his perjury at the trial of his acquaintanceson drug and firearm charges and from his inducement of two other witnesses to perjure themselves in that trial. Upon reviewing the district court's  enhancement of Sinclair's sentence for substantial interference with the due administration of justice, the Tenth Circuit  held "expenses associated with the underlying perjury offense should not form the basis of an upward adjustment." Sinclair, 109 F.3d at 1539. Thus, the Sinclair Court overruled the district court's reasoning, in part, and held that "contrary  to the reasoning of the presentence report, the government's preparation for Mr. Sinclair's perjury trial and the court's  expenditure of time and resources in trying him on that offense cannot be used to support the ... upwardTackett fall within this category where substantiality can be inferred. The defendants  were the only two people who knew about the falsified form, and its relationship to Brian's prosecution. They were the  only source of this information. Truthful testimony from the Tacketts would have changed the course of the investigation  and trial of Brian Tackett. We can infer, therefore, that the Tacketts' procurement and concealment of this fraud was a  substantial interference with the administration of justice.


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The evidence in the record corroborates this inference. After learning of the form 4473, Agent Wilt spent several days  investigating its veracity. With the help of several other agents, Wilt then conducted a four-day electronic surveillance of  the Tacketts, spanning a weekend. A grand jury convened