Thursday, April 11, 2013

Why Citation Counts Can Be Misleading

Mark Tushnet

This morning as I was going through my RSS feed of blogs, I saw a reference to a Salon article about the Republican Party, in which the author mentioned "a willingness to ignore established norms and play 'Constitutional hardball,'" with quotation marks around the latter term but no attribution. (To be clear, I'm not faulting the author for that.) As far as I know, I was the person who introduced that term into constitutional theory, in an article published in the John Marshall Law Review. When I checked it on Lexis, my heart skipped a beat when I saw a use by Senator Cornyn dated a year earlier, but, fortunately, he was citing a prepublication version of my article. Then, when I checked it in the "Major Newspapers" file, I discovered a use by a Canadian politician in 1992 in roughly the same sense. But, I'm willing to defend my claim to priority in constitutional theory.

A citation count for me would miss this use -- and I assume quite a few others. Indeed, so would a citation count for the John Marshall Law Review, where the article appeared as part of an interesting symposium. The reason is well-known within the field of citation studies: Once an idea becomes common currency, that is, extremely widely used, the citation to the idea's originator disappears (unless, I suppose, the originator manages to get his or her name tightly bound to the idea, as in the Coase Theorem, a point that, I am given to believe, was at one point irritating to Judge Calabresi).