Our Purpose

Caselaw taxonomy and the evolution of the legal system

John Elstad, Head of Content Transformation

A bright beacon of hope at the center of our democratic society is the promise of equal justice under law. Central to that promise is the need to ensure that any person — whatever their means or place within society — is assured that they will be treated the same as any other individual under similar circumstances.

One of the ways this is accomplished is to have disputes and violations of law argued and decided based upon legal precedent, where prior decisions are cited around similar points of law, fact, and procedure to justify a consistent decision in the new dispute. Over time and followed consistently, this results in fairness and trust.

Given the sheer volume of cases in our legal system and the number of legal bodies establishing those precedents — state, federal, local courts, and courts of appeal — as well as other areas of government creating law, there is an enormous amount of information to sift through on this journey to determine the most relevant legal precedent. Without sorting this information, transparency and consistency erode. While bringing order to all this is an enormous task, it is precisely here where Thomson Reuters has been a difference maker.

The difficult challenge of helping lawyers more efficiently find appropriate precedents has been a central focus for Thomson Reuters since John B. West established an office in Saint Paul in 1872. In the early years of Minnesota statehood when West Publishing founder John West met with his legal customers, he learned that access to legal information was a challenge. At the time, language gaps created barriers for newly arriving immigrant lawyers and judges, so West created a version of the court practice rules in Swedish.

He discovered that access to case law was costly and hard to come by, so he devised a method for acquiring opinions from a multi-state region to provide more breadth at a fraction of the cost and hired attorneys to build expertise in organizing and structuring this corpus in a way that made sense to a growing legal community — and the West Key Number System was born.

The West Key Number System was bold in its scope of covering the entire breadth of American Jurisprudence. It was organized across federal and state case law, deploying an organizing taxonomy and a series of digests that enabled the researcher to quickly narrow and review relevant summary points of law to find the precedent they needed.

As the taxonomy and body of U.S. law grew, the West Key Number System expanded to bring together caselaw with statutes, regulations, law encyclopedia, and other legal commentary into a comprehensive library that powered the legal profession’s pursuit of the rule of law through better access, transparency, and consistency.

Like the law itself, the real strength of the West Key Number System is its continuous adaptation, consolidating where law is settled and expanding where law is evolving. For decades, our legal expert editors relentlessly reviewed new cases as they arrived and regularly considered the impacts of recent legal decisions on the overall taxonomy.

Today, Thomson Reuters has approximately 1,500 attorney-editors across its products for legal professionals, with approximately 16,000 cumulative years of experience. Every year, Thomson Reuters attorney-editors, with their deep domain expertise, manage changes to more than 100,000 U.S. statute sections, manage a collection of more than 20 million index references, create over 490,000 headnotes, and assign over 550,000 Key Numbers.

Using rigorous editorial standards, the editorial enhancements of our attorney-editors — powered by industry-leading technology — enables legal professionals to make better decisions faster and to act with confidence.

This year is the 150th anniversary of the founding of the West Publishing Company, a predecessor of Thomson Reuters Legal. The mission that launched that firm so long ago is alive and well in Thomson Reuters today. What started as innovations in methods of legal analysis and publishing ingenuity has now been joined by significant investments in innovative computer technology.

Now supported by these powerful technologies, our content and editorial experts are more essential than ever in helping professionals find the information they need to help perfect the pursuit of equal justice. They are steadfast in their commitment to their craft while remaining curious and engaged in innovation to meet emerging needs of the legal community. They are the secret sauce that makes Thomson Reuters the trusted partner to the legal community and I am proud to be a part of this organization.

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