As I was reading COA's decision in Frost v Minnesota Life Insurance Co, I noted the court's citation to DSM-IV (the leading diagnostic treatise for mental disorders). That citation made me recall another case where the Michigan Supreme Court cited to Wikipedia to define a psychological term. In MDOT v Haggerty Corridor, Justice Young relied on Wikipedia to define a psychological phenomenon known as "hindsight bias" (see note 36 of the opinion). In Justice Young's defense, the case had nothing to do psychology; instead he was making an analogy. But it seems that the courts are more willing to cite to Wikipedia, and presumably so are the litigants before them. It seems dangerous to rely on a "source" that can be edited by anyone at any time, regardless of accuracy of the post or expertise of the poster.