Sunonda Paul (defendant) was charged with extortion in connection with an attempt to rob a bank. The bank received an anonymous, handwritten note, directing it to leave $100,000 in a briefcase in a nearby McDonald’s bathroom. When the bank received the note, it alerted the FBI which stationed agents at the McDonald’s and witnessed Paul pick up the briefcase and attempt to leave. After Paul was arrested, Paul gave handwriting samples to the FBI. Larry Ziegler, an FBI document examiner, determined that Paul’s samples matched the note left at the bank. In his samples, Paul had misspelled “restaurant” and the bank manager’s name in the same way that they were misspelled on the note left at the bank. The district court denied Paul’s motion to exclude Ziegler’s testimony. Paul sought to counter Ziegler’s testimony by calling Mark Denbeaux, a law professor who taught evidence, to rebut Ziegler’s claims that the handwritings matched. The district court granted the prosecution’s motion to exclude this testimony. The jury convicted Paul. He appealed on the grounds that (1) Ziegler’s testimony did not assist the jury, (2) Ziegler’s testimony was more prejudicial than probative because the jury believed that Ziegler’s analysis was scientific when it was not, and (3) Denbeaux’s testimony should have been admitted as expert testimony.