legal research artificial intelligence machine learning

From Dusty Tomes to Artificial Intelligence: The History and Future of Legal Research

March 13, 2018 | by Monica Layarda


This week's post looks at the evolution of legal research and its inextricable connection to advances in technology. 

In this high-tech era where google and uber have ascended to verbs, lawyers are often criticized for being slow to adopt new technology. After all, the law itself embodies the very principles of continuity and consistency.

However, in the sea of articles, books, journals and memes comparing lawyers to dinosaurs, it’s easy to overlook how legal practice, and particularly the research process, has historically advanced hand-in-hand with technology. Consider, for instance, how the evolution of printing technology gave rise to the panoply of mass-produced legal materials and finding aids we still rely on to conduct research today, or how digitization allowed for a more targeted case search.

Indeed, history presents a more optimistic picture than often acknowledged: the legal community did successfully adapt to a series of tectonic technological shifts over the last few centuries, albeit slowly, and both the legal process and the law have benefited as a result. In fact, technological innovations that successfully revolutionized the field have historically originated from within the legal circle, including the Ohio Bar Association’s leadership in developing the digital database that became Lexis (now LexisNexis). Lawyers’ participation and feedback will be just as critical to any legal innovation today.

The following presents an abridged history of modern legal research tools. In its most simplified version, the evolutionary history can be broken down to three distinct stages:

I. Analog or print-based era (18th– 1973);

II. Digital era of computer-assisted research (1973-present); and

III. Computational era built upon digitization (beginning in ~2015).

Evolution of legal researchWith current advances in AI, we are approaching the tipping point that will, like its predecessors, lead us to a paradigm shift. But first, let's take a closer look at the history of legal research. 

I. Analog Era: The genesis of modern legal research

It is difficult to pinpoint when the practice of legal research formally began. The first attempt at codifying the common law can be traced at least as far back as Blackstone’s 1765 publication of Commentaries on the Laws of England. The origin of modern case law research, as we know it, has a more identifiable beginning owing to two crucial developments that intertwined in the second half of the 19th century. First, advances in printing press technology and transportation led to an upsurge in the volume and variety of legal materials, beginning with the mass publication of judicial decisions. Second, in response to the first development were the subsequent inventions of case organization systems and other finding tools to cope with the flood of primary and secondary materials. By the turn of the century, therefore, the foundations for modern case law research had been firmly established and the seeds for the volume management problem that continues to beset the legal profession had been planted.

Commentaries of the lawSir William Blackstone (1723–1780). Commentaries on the Laws of England. In Four Books. 4 vols. Oxford: Clarendon Press, 1770.

Modern legal research was shaped dramatically by John B. West, a law book salesman who founded West Publishing Company and played the single most important role in putting in place the framework for reporting, citing and organizing case law. In 1876, taking advantage of the evident, yet largely unnoticed, need among lawyers and judges for a timely and accurate reporting of court decisions, West launched its inaugural news-sheet publication, the Syllabi, which offered the first and most complete current reporting of Minnesota Supreme Court Rulings. Within six months, sensational demand for these reports led the company to quickly expand its coverage to Minnesota’s neighboring states.

In 1879, West launched two of its most influential innovations which continue to underpin the contemporary research system: the National Reporter System (NRS), which introduced the first nation-wide U.S. judicial decision reporting, and the Key Number System, the first indexing scheme that systematically organizes cases by topics and subdivisions. The NRS was a massive improvement on the slow and error-prone State Reports commissioned by state governments. In hindsight, the NRS not only provided U.S. lawyers with an unprecedented and timely access to a cohesive body of case law from all U.S. state and federal jurisdictions, thus facilitating a comprehensive, cross-jurisdictional study, it also gave birth to the concept of a permanent case reference publication and thus secured the primacy of current case studies in the legal research process.

Despite their evident merits, both revolutionary systems met with initial resistance. The courts were reluctant to accept West reporting citations in lieu of the State Report citations until it was clear that West’s reports were the de facto sources used by practitioners. Similarly, the Key Number System—now a legal bread and butter—was initially ridiculed because its (superior) comprehensive indexing was very different from the State Reports organization. By the mid-20th century, however, the need for an accurate judicial reporting system for managing the leap of published cases became so great that courts and lawyers came to fully embrace the NRS and Key Number System. As this twin system achieved universal adoption in the U.S., it too became the dominant paradigm within legal research.

The concurrent launch of the Key Number System with the Reporter signalled the early need for a better data management system to cope with the growing volume of published case law. In 1897, West launched the first volume of the Century Digest, with full utilization of the Key Number System, to organize all state and federal cases from 1685 to 1896 into over 400 topics and 100,000 subdivisions. While these digests were launched to help lawyers stay on top of the ever-expanding case law universe, the enormous volume of digests and case law eventually necessitated the use of various additional finding tools. Shepard’s citators, for instance became the popular tool of choice. Initially launched as stickers printed on gummed, perforated sheets to be pasted onto pages of case law, Shepard’s citators became a multi-volume publication. Besides case law, a myriad of other forms of primary and secondary legal materials (and publishers) further crowded the legal research landscape: statutes and annotations, textbooks, encyclopedia, law practice books, and the list goes on.

Centuries digest

Century Digest, West's Encyclopedia of American Law Copyright 2008 The Gale Group, Inc.

By the 1950s, to cope with the mountains of unwieldy legal materials, legal practitioners had come to rely on a plethora of finding aids, whether indexes, digests, citation tables, citators or concordances.  These finding aids proved incredibly popular but ultimately they were band-aid solutions that did not solve the problem of volume management and knowledge organization. Locating relevant cases, and identifying “good law” became increasingly difficult, laborious and expensive. Information that was once unavailable because it was unpublished was now lost in a sea of information.

II. Digital Era: Self-innovation & attempts at solving the perpetual volume problem

The severity of the research problem eventually led the legal community to actively look towards computers, the emerging disruptive technology of the century, for a more permanent solution. After some initial success with converting case law into a machine-readable form in the early 1960s, the Ohio Bar Association (OBA) formed a working group in 1964 to explore ways to incorporate computer systems into legal research. These efforts proved to be pivotal. The system they tested was subsequently developed by Mead Data Central and launched into market in 1973 as Lexis (now LexisNexis).

Until Lexis, West’s print-based Reporter system was “the only comprehensive system that enabled a legal researcher to locate opinions relating to specific points of law” but Lexis completely revolutionized the legal research process and introduced a new playing field by offering online access to the full text of judicial decisions as well as making them searchable by keywords. Two years later, West entered the digital race with the launch of Westlaw, initially with a head-notes only database to mimic its well-institutionalized print system, but soon realized it was losing the race and upgraded Westlaw into a full-text database. The era of digital legal research, thus, began in earnest with Lexis and Westlaw—and forty years later, the two remain the biggest competitors in the market.

While few lawyers can now envisage legal research without online databases, it took a few decades before they became the norm. Partially, the slow adoption was due to their logistical and technical constraints: limited case coverage, premature computer network infrastructure (the initial access relied on gigantic terminals established over telephone lines), and high acquisition costs—a simple search for the phrase “trial by jury”, for instance, would have cost $5,000 in the 1970s.  Before the end of the 70s, Lexis announced that the pre-eminent American law firms with 100 partners or more had become their clients. This is perhaps unsurprising given the hefty price tag, but this trend importantly renders the staunchly-held stereotype of change-resistant big law historically baseless.

Beyond these hard barriers, the incorporation of such a revolutionary technology also sparked a wider intellectual and policy debate, and even some emotional reactions. Scholars and practitioners pondered whether computers and digital materials should supplement or replace print sources. Some hostile commentators, especially those most invested in the status quo, argued that computer-assisted legal research was a useless, unreliable experiment. Skepticism was especially rampant among law librarians who had built their careers on sophisticated strictures of digests and indexes, which were threatened by digitization. Others, however, welcomed it as a potential solution to navigate the rapidly growing volume of case law and secondary materials.

While these debates were taking place, Lexis and Westlaw saw their client base continue to expand. Over the next two decades, both companies also introduced major product improvements, which in hindsight fuelled further increases in the type and volume of legal materials. These included expanding primary law databases (first, statutes and administrative law, followed by large numbers of previously unpublished appellate decisions), publishing secondary authorities (law review articles and looseleaf services), and building a hypertext function.

The WWW explosion and the sweeping, multi-faceted changes brought by the resultant digital revolution of the 21st century sealed the fates of Lexis and Westlaw. Riding on the shift of global consciousness towards all-digital, it became evident that Lexis’ and Westlaw’s innovative systems were to be the research tools of the modern age. The immediacy and virtually unlimited access and storage of the Internet made the other digital tools of the 80’s and 90’s, most notably CD-ROMs, archaic. A number of favorable developments, thus, fortuitously coincided at the turn of the century, including improvements in computer technology and digital networks which provided a better infrastructure for access, and the prevalence of “free” LexisNexis and Westlaw passwords among law students in the 1990s which added a generational push for technological adoption. By 1994, nearly all major players in the U.S. had access to Lexis and Westlaw.

Digitization, of course, has brought enormous benefits to the legal community. Keyword searches and online citation services allow for a more targeted case search. Back and forth walks to the library and incessant flipping of hundreds of pages of print materials have been streamlined into a dozen finger dances on the trackpad. Steep cuts in publication costs and the easy flow of information have democratized the legal field by allowing for both a greater variety of information sources (such as blogs, podcasts, and social media) as well as a wider and more equal access to legal materials.


LexisNexis Academic Platform, 2018

In this digital age, however, the explosion of legal materials and the globalization of the law has magnified a centuries-old problem of managing volume and locating relevant cases—only the stacks of papers and books that once covered a lawyer’s desk have been replaced by a collection of browser tabs on the computer screen. Perhaps, volume problems are inherent to a legal system that combines both judicial precedent with legislation and protects the permanence of law, which means that the system continuously amasses information as repealed law and overruled cases continue to bear historical, scholarly and interpretive relevance.

The information overload problem of the digital era has only exacerbated this problem. Sophisticated keyword searches frequently return hundreds of results which require hours to search through. The 19th century band-aid solutions, now in digital forms such as Shepard’s and the more contemporary KeyCite, have been exhausted. Worse, the current technology provides little, if any, means to ensure a thorough search through the sea of information. The severity of the legal research problem we have today once again begs the question: are we approaching the tipping point where true innovation is required?

III. The Tipping Point?

Advancements in AI technology have enabled the development of even more sophisticated legal research tools. For example, machine learning systems can analyze the facts and findings from previous case law and use the data to predict how a court might rule in new circumstances. These tools can identify hidden patterns in the jurisprudence that even the most experienced lawyers struggle to precisely quantify, and pinpoint the cases that are most relevant to the scenario facing a researcher. This technology could lead to the permanent solution to the centuries-old problem of managing the plethora of legal materials and identifying relevant case law.

With a flurry of AI technologies entering the legal market, thorough planning, a long-term vision and a healthy dose of caution are crucial to long-term success. Yet, as Peter Drucker wisely cautions, “…in times of turbulence, the biggest danger is to act with yesterday’s logic.” The legal community has historically showcased its foresight and willingness to disrupt, innovate, and improve. By harnessing emerging technologies in the past, it has not only avoided Kodak-esque redundancy, but also advanced the legal practice and the law. It is now for you to decide if the time to lead the change in the 21st century is finally upon us.

 Tax Foresight Blue J Legal

Tax Foresight by Blue J Legal, 2018

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Works Cited

“West Group History.” International Directory of Company Histories (2000). Available at Accessed March 10, 2018.

Berring, Robert C. “Full-Text Databases and Legal Research: Backing into the Future.” Berkeley Technology Legal Journal 27 (1986). Available at: Accessed March 5, 2018.

Bing, J. “Let there be LITE: a brief history of legal information retrieval.” European Journal of Law and Technology, Vol. 1, Issue 1 (2010).

Foster, Lynn and Bruce Kennedy. “Technological Developments in Legal Research.” The Journal of Appellate Practice and Process, (2000): 275-303.

Grossman, Bruce. Legal Research: Historical Foundations of the Electronic Age. Oxford: Oxford University Press, 1994.

Hanson, F. Allan. “From Key Numbers to Key Words: How Automation Has Transformed the Law.” Law Library Journal (1992): 563-600.

Harrington, William G. “A Brief History of Computer-Assisted Legal Research.” Law Library Journal 77, (1984-1985):  543-557.

Kauffman, S Blair. “Electronic Databases in Legal Research: Beyond LEXIS and WESTLAW”. Yale Faculty Scholarship Series, Paper 1293 (1987). Available at Accessed March 5, 2018.

Marke, Julius J., Richard Sloane, and Linda M. Ryan. Legal research and law library management. New York: Law Journal Press, 2007.

Mills, William R. “The Decline and Fall of the Dominant Paradigm: Trustworthiness of Case Reports in the Digital Age.” 53 New York Law School L. Review, Rev. 917 (2009). Accessed March 10, 2018.

Stewart, June. “CALR's Role in the Legal Research Process.” Legal Reference Services Quarterly (1996).

Wardell, Kayleen. “From Caveman to Casebase: The Evolution of Legal Research Through the Technological Age.” Paper presented to the Australian Law Librarians’ Association (ALLA) Evolution Conference, Darwin. Available at Accessed March 2, 2018.

Tags: legal research artificial intelligence machine learning


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