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Go ahead and Google–then do a subject-based search


We all love to Google. And most of the time, even if we aren’t on Google, we search like we are, even on Westlaw and Lexis. That’s certainly one important part of research—Googling, or full-text searching, on Westlaw and Lexis (which includes plain language, natural language, terms and connectors, and Boolean searching). But there’s another way to search called subject- based searching, which can, and should, be a companion to your full-text searching.

Here are some ways you can do subject-based searching when you’re digging into legal research.

1. Check the index and TOC. The index and table of contents, or TOC in shorthand, are common tools from the print days, and for some sources, Westlaw and Lexis have incorporated them into electronic legal research.

While they may not be as necessary as they once were when legal research was exclusively done with print, if they’re available, they can be helpful to your electronic legal research. In particular, you can do subject-based searching in your statutory research by using the index to find a statutory section on point and then using the table of contents to see the statutory scheme. That allows you to review the sections near the section you’re researching so that you can quickly find others that may also be relevant.

The index is a helpful tool for many reasons, one of which is that it includes some words that aren’t in any statutory section. It also connects you to the synonyms of those words and the statutory sections that address those synonyms. The index can also help you narrow down statutory sections that have a term that’s common to the sections that are relevant in their usage of the common term you’re looking for.

The TOC is helpful because related statutory sections are usually close to each other. So once you find one statutory section on point, others that apply may be nearby.

2. Next up: Westlaw topics and key numbers. These have been around since the print days, when they were published in books called digests. Now you can also find the topics and key numbers electronically, exclusively on Westlaw.

The West key number system consists of the topics listed alphabetically, with the key numbers listed under each topic in numerical order. Each key number is assigned a sub-topic. Even today, new topics and sub-topics are added to the West key number system as new areas of law emerge.

I like to think of the topics and key numbers as hashtags connecting all the cases on Westlaw that have head notes that have been “tagged” with the same topic and key number. This helps gather them in one place for researchers.

The tags are even hyperlinked. When you click on a hyperlinked topic and key number, you’ll find a list of other cases that have been tagged to that same topic and key number. You can filter by jurisdiction, time period, and more. Unlike hashtags, the tagging can’t be done by just anyone. Westlaw hires professionals to write the head notes for the cases and tag topics and key numbers to the head notes.

3. Use the one-good-case method. This is the superior legal research strategy for finding a case in one jurisdiction that’s similar to a case in another jurisdiction, and the main tools you use in this method are a topic and key number.

Citators are helpful research tools, but they’re limited to finding cases only that cite one another. An Oklahoma state court case may not cite a Utah state court case but could still be similar enough to be helpful in your research.

Say you’re in the beginning stages of the research process of a state law question and are looking in a national legal encyclopedia. Since the encyclopedia isn’t comprehensive in the cases that are on point for a given entry, the only good case you can find is from another jurisdiction.

The one-good-case method is the most efficient way to check to see if there’s a case on point in your jurisdiction.

All you need to do is:

  • Look up the good case you found in Westlaw.
  • Read the head notes and find the one that’s most on point with your research question.
  • Click on the topic and key number tagged to that head note.
  • Change the filtered jurisdiction to the one you want to find a case in.

And voilà! Essentially you’ve made yourself a custom digest of cases to look through for your research.

If there’s a similar case in your jurisdiction on point, it should appear.

4. Turn to Lexis’s topics. As I mentioned, topics and key numbers aren’t on Lexis. However, Lexis has created topics and sub-topics similar to the areas of law you’d find in the West key number system, though I’d argue that the sub-topics aren’t as specific as the ones you can find in Westlaw’s topics and key numbers.

Like on Westlaw, these sub-topics are “tagged” to specific headnotes from the cases. Unlike Westlaw, there are no numbers associated with any sub-topics. And the head notes are direct quotes from the cases instead of head-notes written by professionals.

5. Browse the subjects. Both Lexis and Westlaw allow you to browse the subjects they’ve created. In Westlaw, you can select browse key numbers. This takes you to the outline of the West key number system, and you can look at all the topics listed together.

You can also narrow down by clicking the relevant hyperlinks to find a specific topic and key number that works for your issue. Then you’ll be shown all the cases on Westlaw that have been tagged to that topic and key number. You can apply standard filtering features, such as jurisdiction, date, and so on.

In Lexis, you can select browse topics, similar to Westlaw. Once you’ve found the narrowest topic that’s useful for your research, you can choose it as a filter to search for cases. Or you can select “get documents” and browse the cases that have been tagged to that topic adding additional filtering options, such as by court, state, timeline, and so on.

The pros and cons

Subject-based searching has its strengths and weaknesses. It’s easier to search for concepts or topics, and someone has already done a lot of the research work for you by looking at the documents beforehand and categorizing them. However, subject-based searching relies on someone else’s categorization and isn’t focused on specific phrases, like many that judges might use in opinions.

Maybe you know you want cases that talk about a specific phrase in your state’s laws, perhaps about a “limited purpose public figure” in defamation law. That specific phrase is so narrow that it doesn’t have a topic and key number. Putting it into a search bar to do a full-text search of your state’s cases instead will turn back more-specific results for your research.

Subject-based searching also doesn’t include cutting-edge topics. For example, drones and unmanned vehicles are so new that neither has been assigned a topic and key number yet.

So when should you use subject-based  searching? I recommend it when you’re:

  • Looking for a concept
  • Unfamiliar with an area of law
  • Not confident full-text searching is retrieving everything

Just remember—I’m not saying not to search in Lexis and Westlaw like you search in Google; you can, but using a combination of both subject-based and full-text searching is often the most effective way to search during the research process.