Questionable citation of Wickedpedia by court opinion

Because of Wikipedia's unreliability on controversial issues, I have many times condemned authoritative citation of Wikipedia by court opinions, scholarly journal articles, etc.. On the Volokh Conspiracy blog, Eugene Volokh now has an article questioning citation of Wikipedia by a federal appeals court opinion:

Courts have cited Wikipedia over 300 times, and many of those cites are in my view just fine when the citation is for a tangential and uncontroversial matter. But the Seventh Circuit's use of Wikipedia in Rickher v. Home Depot, Inc., handed down Monday, strikes me as troubling.

The key issue as to one part of the plaintiff's lawsuit was the definition of "wear and tear." The plaintiff cited Webster's II New College Dictionary and Random House Webster's College Dictionary, which defined the term as “Depreciation, damage, or loss resulting from ordinary use or exposure” and “Damage or deterioration resulting from ordinary use; normal depreciation,” But the court disagreed:

Although it is true that dictionary definitions of “wear and tear” often employ the word “damage,” that does not mean that damage and “wear and tear” are synonymous. Wear and tear is a more specific phrase that connotes the expected, often gradual, depreciation of an item. See Wear and Tear, http://en.wikipedia.org/wiki/Wear_and_tear, last visited May 30, 2008.

[Wikipedia said -- ]

It is a form of depreciation which is assumed to occur even when an item is used competently and with care and proper maintenance. For example, friction may erode a hammer’s head. In the normal use of a hammer for its designed task erosion is impossible to prevent, and any attempt to eliminate this erosion would make the hammer useless. At the same time, it is expected that the normal use of a hammer will not break it beyond repair until it has gone through a certain amount of use.

A subtle difference, but one the Seventh Circuit thought to be quite important, and that does indeed appear to me important to the course of litigation.

More details are in Volokh's article. I have commented extensively in the comment thread under the article and I am continuing to add comments. Later I may hijack the thread for a tirade against Wickedpedia.
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