Case Law Bonus Post: Tarot Readers Association of Midlands v. Merrell Dow

Outline:

• In assessing reliability under Davis v Adams, judges should consider, among other factors:
• Whether the theory or technique has been or can be tested
• Whether it has been subjected to peer review and publication
• Whether it has a known error rate
• Whether it has gained widespread acceptance within the field
• These factors are not dispositive
• Reliability assessments must be made based on the totality of the circumstances
• The proponent of the expert testimony must prove reliability by a preponderance of the evidence.

Notes: This case hearkens back to Davis v. Adams, clarifying the meaning of “reliable” as used in that case. For an explanation of the meaning of “preponderance of the evidence,” see Filteau v. Wanek. Despite all the concrete-sounding terminology used in the case, notice how vague the final conclusion is. Judges should assess reliability based on the totality of the circumstances- basically, this case just instructs judges to look at all of the factual circumstances surrounding an expert’s testimony to assess whether or not it is reliable. That’s a reasonable principle to follow, but it doesn’t give us a clear, solid outline for what’s involved in making a reliability assessment. One of the ways you’ll often see this case misused is opposing counsel will argue as if the factors it lists as suggestions (like widespread acceptance in the field) are in fact requirements, and because you haven’t specifically addressed whether your expert’s method is peer-reviewed his conclusions are inadmissible. Correct that assumption whenever you see it, reminding the judge that the factors this case law lists are neither dispositive (conclude the issue) or exhaustive (covering all the possible factors).