10th Circuit Upholds Exclusion of Computer Expert Testimony Under Rule 704(b)

The Tenth Circuit has published an opinion upholding the exclusion of testimony from a computer expert in a child pornography case. The witness proposed to testify, based on the file structure of the defendant's hard drive, that the material on the defendant's computer was likely acquired in a "porn fishing expedition with no particular calculation toward any particular type of material, other than generally sexually explicit material." The appellate panel upheld the trial court's ruling that the proposed testimony constituted forbidden expert opinion on mens rea under Fed. R. Evid. 704(b). See United States v. Shaffer, No. 06-3145 (10th Cir. Jan. 3, 2007) (Murphy, McKay, & Gorsuch, JJ.).