In 1990, Pierre N. Leval, then serving as a federal judge, ran across an unexpected stumbling block while crafting a Harvard Law Review article about the “fair use” doctrine of American copyright law. To wit, he was worried that quoting his own cases, exactly as they had been published in law volumes, might itself run afoul of then-narrowing fair use guidelines, which govern how much of someone else’s copyrighted work you can lawfully quote without asking permission.

Last week, Leval—now serving as a senior judge on the 2nd U.S. Circuit Court of Appeals—finally got his best shot yet at restoring balance to “fair use” law, in an expansive Court of Appeals decision that reaffirmed the lawfulness of Google Books, a project that involves the unlicensed scanning and online search of whole libraries. A similar decision against the plaintiffs in another case, this one involving a non-for-profit research database, had come down last year. But last week’s 3–0 Google Books decision broke ground by straightforwardly favoring the book-scanning project’s wholly commercial parent company (still known as “Google,” but now a division of Alphabet Inc.).

In draft form, Leval’s 1990 article explored appellate court opinions focused on two of his own earlier opinions as a federal judge; one case centered on a biography of J.D. Salinger while the other concerned an exposé of Scientology founder L. Ron Hubbard. Leval’s earlier district court opinions had quoted heavily from unpublished copyrighted materials from both Salinger and Hubbard. But given developments in copyright law, Leval mused in a footnote, he couldn’t be sure that quoting those earlier opinions (and their appendices) again would be protected by fair use. “I have accordingly deleted the illustrative quotations. Interested readers are referred to the district court opinion, which sets forth numerous examples,” he wrote.

Leval thus kept himself and the law review on the right side of the then-understood line of fair use. But even in its modified form, his article has helped shift the course of American fair use law over the past 25 years. The fact that he authored the Google Books decision last week is a rare convergence of legal and poetic justice.

Friday’s ruling is a big deal not just for search engine giants, copyright lawyers, authors, and publishers, but also for ordinary people. Only a generation ago, doing scholarly research in the way that Google Books now makes possible was a game only academics could play. At the time Leval was first tackling fair use doctrine in his district-court cases, university professors, graduate students, and even muckraking biographers had to master arcane skills (managing card catalogs, for example) in addition to their subject-matter expertise. Plus, they had to live near, or arrange access to, the holdings of research libraries, just to make sure they didn’t miss any relevant materials. (The most entertaining, contemporaneous depiction of this hermetic, pre-Internet world is A.S. Byatt’s 1990 Booker Prize–winning Possession, set in the late 1980s. The book’s fictional depiction of literary detective work and the hunt for rare, unpublished manuscripts is only slightly satirical.) Even scholars with full access to troves of material in university libraries or museum collections couldn’t do the kind of digital analysis (even if sometimes flawed) that Google’s full-text searches now extend potentially to everyone.

So it was unsurprising when Google Books prevailed in 2013 in U.S. District Court—almost exactly two years before Friday’s appellate decision. “Google Books has become an essential research tool,” the district court found that year, “as it helps librarians identify and find research sources, it makes the process of interlibrary lending more efficient, and it facilitates finding and checking citations.”

Furthermore, the district court had added, “Google Books has become such an important tool for researchers and librarians that it has been integrated into the educational system—it is taught as part of the information literacy curriculum to students at all levels.” The New York Times led its report by noting that “today, when people expect to find almost anything they want online,” Google Books already “seems like an unsurprising and unavoidable part of today’s Internet.”

Yet avoiding this seemingly “unavoidable” aspect of today’s Internet has been precisely why the plaintiffs (some of them authors and publishers, though not all of their peers agree) have spent more than a decade, and millions of dollars, pressing litigation in this case and similar cases. In fairness to the Authors Guild and the co-plaintiffs, their arguments—based largely on the fact that Google is scanning the full texts of copyrighted books and making those texts searchable, but also on the fact that Google is indisputably a commercial enterprise—would certainly have had more traction in the pre-digital era. Historically, fair use defenses in copyright cases have required courts to apply, on a case-by-case basis, the so-called four-factors test, which considers:

1) the purpose and character of the use
2) the nature of the copyrighted work
3) the amount and substantiality of the portion copied, and
4) the effect of unlicensed copying upon the potential market.

This framework was formally added to the U.S. Copyright Act in 1976, but its roots go back much deeper into American copyright law.

In a 1994 case, the high court (relying on Leval’s law review article, among other sources) concluded 2 Live Crew’s parody version of the Roy Orbison hit “Oh Pretty Woman” might well be a protected fair use under copyright law. A key question to be asked regarding whether a copyright of protected source material is justified is whether the use of the material is “transformative.” As Justice David Souter wrote for the court:

Although such transformative use is not absolutely necessary for a finding of fair use … the goal of copyright, to promote science and the arts, is generally furthered by the creation of transformative works. Such works thus lie at the heart of the fair use doctrine’s guarantee of breathing space within the confines of copyright … and the more transformative the new work, the less will be the significance of other factors, like commercialism, that may weigh against a finding of fair use.

As a result, he concluded, “It was error for the Court of Appeals to conclude that the commercial nature of 2 Live Crew’s parody of ‘Oh, Pretty Woman’ rendered it presumptively unfair.” Souter carefully appended the lyrics of both songs to the Supreme Court opinion; presumably, he didn’t think he was infringing in doing so. Of course, 2 Live Crew’s “Pretty Woman” parody did not sound exactly like Roy Orbison’s original song, so it’s perhaps easier, now, after a couple of decades, to see how the rap parody version was “transformative.”

But what about Google Books’ scanned text from university libraries and other repositories? The whole value of Google Books as a research tool depends on the extent that the texts made searchable are as accurate as possible (ideally, identical down to the letter). Can that be transformative?

Affirming the district court’s 2013 findings, Leval explained at length in Friday’s decision what precisely is transformative about Google Books—primarily, the search service has taken pains to uncouple searching book texts from the actual reproduction and distribution of those books, so that the market for sale of the copyrighted works is (in the absence of solid evidence to the contrary) undiminished.

“Google’s making of a digital copy to provide a search function is a transformative use, which augments public knowledge by making available information aboutPlaintiffs’ books without providing the public with a substantial substitute for matter protected by the Plaintiffs’ copyrighted works or derivatives of them,” Leval concluded. The “snippet function,” which provides very small excerpts of the contextual text in search results, doesn’t pose a risk to the market for copyrighted works, Leval found in the course of a thorough review of the district court decision.

The Authors Guild, unsurprisingly, has said it will appeal this latest 2nd Circuit decision to the Supreme Court. But it will be quite surprising indeed if the Supreme Court gives these plaintiffs what they’re asking for, given how the high court has interpreted fair use ever since Judge Leval, in a cautiously noninfringing law review article, seeded the modern transformative evolution of fair use.

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