Defense Expert Testimony On Defendant’s Motive To Take Photographs In Child Pornography Case Excluded

In trial for the production, distribution and possession of child pornography, affirming exclusion of defense expert testimony that the defendant “was not a pedophile and was not sexually attracted to young girls” to explain his “motive for taking the photographs” as irrelevant to the issue of the “sexual character” of the images, in United States v. Wallenfang, 568 F.3d 649 (8th Cir. June 9, 2009) (No. 08-2393)


In some cases the motive of the defendant may be relevant evidence. For example, motive may be relevant in a bank robbery case. See, e.g., United States v. Feldman, 788 F.2d 544, 557 (9th Cir. 1986) (in bank robbery case, evidence that defendant “owed ‘substantial sums’ was relevant to show motive”). In other cases, the motive may be irrelevant to any matter of consequence in the case. In other words, the commission of the crime does not turn on the motive. A receipt Eighth Circuit case explored the relevance of the defendant’s motive based on the anticipated testimony of a defense expert.

In the case, defendant Wallenfang's online identification came to the attention of a child victim analyst at the National Center for Missing and Exploited Children (NCMEC). The online identity "phluvr" had posted images of “prepubescent female with brown hair in various stages of dress wearing pantyhose or thigh-high stockings.” The Internet Protocol address was identified. The information was provided to law enforcement. After further investigation, a search warrant was executed at the defendant’s residence and evidence indicating the production, distribution and possession of child pornography was seized.

After charges were filed, the defendant offered to call a mental health expert to testify that the defendant was not a pedophile and was not sexually attracted to young girls” to explain his “motive for taking the photographs.” The government moved to exclude the defense expert. The trial court ultimately excluded the expert testimony as irrelevant:

“The fact is, of course, that you could violate this statute with any number of motives. They could be financial. They could be trying to harm someone. They could be any number of things, all of which may include pedophilia, but don't need to. And, accordingly, the motive behind the conduct that violates these statutes is not an element of the offense and when not raised by the government, it is simply not material to any issue that's before the court in this case.”
Wallenfang, 568 F.3d at 653-54 (quoting trial court ruling). The defendant was convicted on three counts by the jury and acquitted on one receipt of child pornography count. The defendant was sentenced to 320 months in prison. On appeal, he contested the exclusion of his defense expert.


The Eighth Circuit affirmed the exclusion of the defense expert. As the circuit explained:

“Here, we concur in the district court's well-reasoned and thorough analysis excluding [defense expert] Dr. Rypma's testimony. The issue of Wallenfang's ‘motive’ in producing, distributing, and possessing the photographs at issue is immaterial and irrelevant. Instead, ‘the relevant factual inquiry in this case is not whether the pictures in issue appealed, or were intended to appeal, to [Wallenfang's] sexual interests but whether, on their face, they appear to be of a sexual character.’ [United States v.] Kemmerling, 285 F.3d [644,] 646 [(8th Cir. 2002)]. Moreover, Wallenfang argues that the government ‘opened the door’ when it cross-examined Stevens and inquired into whether a child molester might have a different focal point when viewing a photograph of a naked child than Stevens would. But Wallenfang did not object to this line of questioning. In fact, the government's questions countered Stevens's testimony that the focal point of the photographs was the legs and feet of the child. Such questioning was appropriate because, as noted supra, the relevant inquiry was not whether the photographs appealed to Wallenfang's sexual interests but whether they were of a sexual nature.”
Wallenfang, 568 F.3d at 660-61.


In addition to considering whether the motive was relevant or not, the Wallenfang case demonstrates the exclusion of expert testimony without assessing the admissibility of the evidence under the expert rule, FRE 702. Normally, the expert testimony is inadmissible under FRE 704(b) to show “the mental state or condition of a defendant in a criminal case,” unless the defendant claims he was suffering under some mental defect, as the trial court had observed.

Federal Rules of Evidence
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