“Nothing so completely baffles one who is full of trick and duplicity himself, than straightforward and simple integrity in another.” Charles Colton

"Duplicity" is improper. Arising from joining distinct offenses in one count, duplicity analysis involves two steps. The first step involves statutory interpretation, and the second considers duplicity doctrine policies.

To elaborate, the first step ascertains whether an indictment properly charges a violation of the pertinent statute. To do this, courts look for legislative intent in a statute's plain text, legislative history, and judicial precedent. The second step examines concerns about charging in one count what could be several independent charges. A finding of duplicity is avoided only when these concerns are not implicated.

There are several purposes for prohibiting duplicity. First, based on a concern for accurate verdicts, duplicity can produce uncertain general verdicts of guilt which may conceal a finding of guilt as to one crime and not guilty as to another. The Second, concerned again with accuracy, to avoid the risk that the jurors may not have been unanimous about any one of the crimes charged. Third, to protect the defendant's right to notice of the charges, and to ensure notice is adequate. Fourth, to provide for appropriate sentencing. Finally, to protect against double jeopardy. These policy considerations overlap with concerns for fundamental fairness and due process. These areas of law may actually prohibit combining what could be several independent charges into a single count, even if a statute appears to allow it.

United States v. Thomas L. Root (3d Cir. 2009).