Do Copyright Professors Pay Attention to Economists?: How Empirical Evidence on Copyright Piracy Appears (or Not) in Law Literature

One of the great empirical questions of early 21st century intellectual property has been whether online copyright infringement causes harm to authorized sales of copyrighted works. Beginning in 2003, economists turned their attention to studying this question empirically. As of early 2022, there have been 34 empirical studies published in peer-review journals on whether online copyright infringement harms authorized distribution of copyrighted works. Of these 34 studies, 29 have found that online copyright infringement causes statistically significant harm to legitimate sales. Only five (5) peer-reviewed studies found no harm to legitimate sales. Given the weight of empirical studies, it is fair to say that there is a consensus among economists that online copyright infringement does harm legitimate sales of copyrighted works. That consensus is reflected in the economics/management literature, where a supermajority (78%) of citations are to papers finding statistically and economically significant harm from copyright piracy. But the world seen through law reviews tells a different story: in the law literature a majority of citations are to the five papers finding no harm, with almost half of all citations being to just one 2007 study finding no harm. Most of the 29 studies finding statistically and economically significant harm from copyright piracy are ignored in the law literature. The paper discusses different possible explanations, including how citations beget citations in law literature, whether law academics are insensitive to the importance of peer-review, the false objectivity of “both sidesism,” and the possibility of ideological preferences shaping citations.