The Law Librarians blog posted about a paper by James Donovan, Carol Watson, and Caroline Osborne on SSRN called The Open Access Advantage for American Law Reviews.
From the article:
In answer to law faculty questions about how participation in an open access repository will affect the works’ impact, the present research offers a definitive reply. When looking at citation by other law reviews to all the author’s work, the averaged increase in citations in flagship journals is 53%. In general, half of these cites will be dispensed in the first six years after the article’s publication. OA articles will attract more attention earlier in the lifecycle of the publication, and endure longer on the intellectual stage.
For authors, the message is clear: The open access advantage is real, sizable, and consistent. The minimal effort to upload an article onto an OA platform such as SSRN or a school’s repository pays rich dividends in the currency of subsequent citations in law reviews and court decisions.
From the abstract:
Articles available in open access formats enjoy an advantage in citation by subsequent law review works of 53%. For every two citations an article would otherwise receive, it can expect a third when made freely available on the Internet. This benefit is not uniformly spread through the law school tiers. Higher tier journals experience a lower OA advantage (11.4%) due to the attention such prestigious works routinely receive regardless of the format. When focusing on the availability of new scholarship, as compared to creating retrospective collections, the aggregated advantage rises to 60.2%. While the first tier advantage rises to 16.8%, the mid-tiers skyrocket to 89.7%. The fourth tier OA advantage comes in at 81.2%.
Citations of legal articles by courts is similarly impacted by OA availability. While the 15-year aggregate advantage is a mere 9.5%, new scholarship is 41.4% more likely to be cited by a court decision if it is available in open access format.