Error to Exclude Expert Testimony Based on Expert’s Lack of Personal Experience

United States v. Liu, No. 12-30105 (May 6, 2013) (Davis, Graves, Higginson)

Wen Chyu Liu, aka David W. Liou, challenged his convictions to steal trade secrets and perjury. The panel held that the district court erred when it excluded expert testimony. However, the defendant’s failure to proffer the excluded testimony made it difficult to determine whether the testimony in question would be of any true help to the defendant’s case.  Thus, the exclusion did not affect the outcome of the trial and the panel affirmed.

Liu was accused of stealing classified info from the Dow Chemical Company in order to sell the trade secrets to Chinese companies for his own profit. The former Dow employee claimed at trial that he had developed a new process for making the chlorinated polyethylene compound known as “Tyrin CPE” and did not use any Dow-derived information in its production. Testimony from co-conspirators and plagiarized material proved the defense otherwise.

Liu argued that the court erred in excluding his expert witness’ testimony. The panel agreed with Liu that the expert’s lack of personal experience, which was the court’s concern, should not ordinarily disqualify an expert, so long as the expert is qualified based on some other factor provided by Rule 702. The panel could not determine whether the witness’ testimony would have been beneficial to the defense because the defense did not proffer what that testimony would have been and because the evidence against Liu’s scheme was overwhelming. The panel concluded that exclusion of the expert testimony did not affect the verdict.

In regards to Liu’s perjury conviction, the panel affirmed. The panel held that testimony by two of Liu’s co-conspirators, Stoecker and Wheeler, paired with documents showing the funding source for Stoecker’s trips to China was sufficient evidence for Liu’s perjury conviction.

Thanks to FPD Intern Matthew Gonzalez for this post.