WESTLAW DIGEST SYSTEM™ AND
LEXIS HEADNOTE SYSTEM™ 1

October 28, 2011
Kathleen M. Sasala, Esq., Librarian


Westlaw Digest System:

As you may already know, all West case reporters organize cases and many other resources, such as CJS and American Jurisprudence 2nd, into standardized bites of information that make up West’s Digest system. This Digest system easily facilitates the discovery of cases and secondary sources published by West because it employs a universal system of topics and key numbers for all jurisdictions covered by West. I like to think of it as a huge outline of domestic United States law that enables users to find cases in an ever-growing body of legal jurisprudence. While we used to have to use print digests (e.g., state, regional, decennials) to find cases manually, West carried over its Digest system to Westlaw,2 which is what we will discuss today on Westlaw.com.3

Key Number Search: Westlaw provides quick entree to its Key Number system through a search engine at the top of the page. This search engine allows you to use terms and connectors to search for topics and key numbers that are relevant to your legal research. You can simultaneously search all Westlaw jurisdictions, or pick and choose as many state and federal jurisdictions or specialized state and federal legal topics as you want. When you hit the Search button, Westlaw retrieves a list of topics and key numbers with check boxes beside each entry. Your next step is to choose one or all of the entries that you want, and hit the Search Selected button. Westlaw will then retrieve lists containing the captions and summaries of all cases within those topics and key numbers. Each summary is hyperlinked to the full text of the document if you want to review the resource in full.

Browse the Digest: Alternatively, Westlaw allows you to browse its alphabetical outline of over 400 Digest topics and expand each one down to its lowest level of key numbers using + signs. Once you have found all of the topics and key numbers you would like to search, you can check off the boxes next to the relevant entries, and click the Search Selected button. Once you do that, Westlaw takes you to a screen where you can further refine your search by jurisdiction or date, add optional search terms and connectors, include ALR’s, law reviews and other references in your search, and rank your search results by either the most recent cases or the most cited cases. Once you set all of the parameters you would like, just click the Search button, and Westlaw will return a list of summaries of cases that are relevant to your research.

Search Using a Specific Topic and Key Number: If you already know the topic and key number relevant to your research, you can enter it quickly in a box in the right hand bottom corner of the Key Number outline. For example, if I wanted to search for the topic of Adoption (which is topic no. 17), and the key number for the Status of adopted persons in general (which is key number 18), I would type in 17k18 to retrieve relevant cases.

Custom Digests: Westlaw also provides the ability to create a Custom Digest. First you must choose a database in which to search. Then, you can click the Custom Digest link at the top of the screen. This takes you to Westlaw’s master outline of topics and key numbers where you can expand the + signs to drill down to relevant key numbers and eventually check off all of the topics and/or key numbers you want to search. You then hit the Search Selected button, which takes you to a screen where you can further refine your search by jurisdiction or date, add optional search terms and connectors, include ALR’s, law reviews and other references in your search, and rank your search results by either the most recent cases or the most cited cases. Once you set all of the parameters you would like, just click the Search button, and Westlaw will return a list of summaries of cases that are relevant to your research. Again, each case is hyperlinked to its full text.

KeySearch: If you do not know how to use the Digest system or would like Westlaw to help you create a search, this is the option to use. According to Westlaw, Westlaw’s KeySearch option “identifies the terms and key numbers that are most relevant to your legal issue and creates a query for you.” (www.westlaw.com). You start a KeySearch by browsing a screen of over 40 legal subjects such as bankruptcy, employment law, family law, intellectual property, securities law, or transportation. You then click the folder icon next to the general topic you want to research. Depending on how broad the subject is, you can continue to repeat this process with sub-folders until you reach an eventual subject that you want to search. At that point, you will see a KeySearch screen where Westlaw asks you to choose jurisdictions, secondary sources, OR journals/law reviews in which Westlaw will eventually conduct a search. To attempt to narrow the field of results up front, Westlaw also allows you to add additional search terms before clicking the Search button. If you choose the case law options, your search will return a list of cases from a combination of topics and key numbers related to the subject you chose. In other words, you narrow the topic, but Westlaw creates the query in the background, saving you the work of trying to craft a search with search terms and connectors.

Hyperlinks from Found Cases: If you find a case or resource that is helpful to your research, you can easily jump by means of internal hyperlinks from that case or resource to other cases on the same topics and key numbers.

Keyciting with Topics and Key Numbers: As noted above, Westlaw has assigned independent, sequential numbers for each topic and key number sequence that it assigns to cases. Although it sometimes creates confusion with Lexis, Westlaw also calls these numbers Headnotes. For example, the first sequence of a topic and key number combination in a Westlaw case might be the topic of appeal and error and the key number for transcript or return (i.e., 30k612). Westlaw would assign this sequence a Headnote number such as HN1, HN2, HN3... These headnote numbers can be helpful in finding subsequent authorities when you KeyCite a case that stands for multiple legal propositions and/or contains many references to different topics and key numbers. Each of these independent numbers directly hyperlinks to all citing references for that number. Alternatively, you can KeyCite a case in full, and review the references to HN1, HN2, HN3, etc. in the KeyCite report, and view only those decisions that are relevant to your legal issue.


Lexis Headnote System:

Lexis also provides a unique way of categorizing and classifying cases to allow users to find additional authorities on similar facts and/or legal issues. Lexis organizes the cases it reports by assigning them to particular topics and sub-topic that break down the practice of law into manageable subjects. Unlike Westlaw, Lexis has not assigned numbers (what Westlaw calls Topic numbers and key numbers) to any topics or sub-topics in its legal taxonomy. Stated otherwise, Lexis relies solely words to designate topics and sub-topics. The only numbering system Lexis uses employs simple headnotes (e.g., HN1, HN2, HN3) within each case that allow for hyperlinking to other relevant cases on the same topics. We will delve deeper into how this system works on Lexis.com online today.4

Topic Searching: Like its biggest competitor, Lexis offers you the choice of starting your legal research very generally with a legal topic. Lexis offers two (2) different options to facilitate this method. The first option is to search for a topic with a key word or phrase. This is more like a natural language search since this option does not recognize Boolean or universal search characters. This search will retrieve topics anywhere within the Lexis classification system, regardless of the practice area.

Alternatively, Lexis offers a second option that allows you to browse its hierarchy of alphabetized legal topics and expand relevant topics by clicking on + signs to drill down to more narrow subjects that succinctly define your research issue. At any point, you can click on an information button next to a legal topic to retrieve a summary of the content that is covered. Once you reach a point where you would like to conduct a search, Lexis provides a search screen with a number of templates to refine your search. Various options include choosing a jurisdiction or jurisdictions, choosing one or more databases, and adding optional search terms (using either terms and connectors or a natural language query). Once you have set all of these parameters, you just hit the Search button, and Lexis returns a result list of cases that match all of your pre-defined criteria. Instead of defining jurisdiction(s), source(s) and optional search terms, you can simply choose a jurisdiction, and add an optional date before hitting the Search button. Lexis will then retrieve all headnotes and cases on the topic you have chosen.

Unless you refine your topic down to a more narrow issue, these searches tend to retrieve a lot of cases. When your search retrieves over 3,000 results, you will receive a message from Lexis asking you to refine or edit your search.

Hyperlinking from Found Cases: If you have found a good case on Lexis, you can use the headnotes at the top of that case to find other relevant cases. After the text of each headnote, you will see the phrase “More Like This Headnote.” Clicking that hyperlink will take you to a search screen that allows you to identify a jurisdiction or combination of jurisdictions, as well as specify a date or date range, to narrow the pool of results. Lexis will then return a list of cases, each of which contain those same headnotes in Digest view (i.e., abbreviated). Nomenclature can be misleading, but do not confuse this with the Digest system on Westlaw discussed above. Each case can then be reviewed in full by clicking on the hyperlink embedded in the caption of the case.

Shepardizing with Headnotes: As you may already know, many cases that Lexis reports contain multiple headnotes, often on a diverse array of legal subjects. Since you may only be interested in one (1) or two (2) of these subjects, you may want to restrict your review of subsequent cases by Shepardizing and looking at only those cases which contain the same headnotes. Lexis makes this very easy to do. The easiest way is if there is a direct link to “Shepardize: Restrict by Headnote” right next to the headnote that pertains to your research. Although not every headnote offers this option (because not every case has been cited subsequently for every headnote), clicking it when it is available retrieves a list of citing references that also contain the same headnote number. Obviously, this functionality makes Shepardizing extremely efficient and helpful.

Alternatively, you can make note of the pertinent headnotes in a case, run a full Shepard’s report, and then review the Lexis summary at the top for a break-down of the number of citing cases for each headnote. Although you may not need this feature if your original case has only a couple of headnotes or a short Shepard’s history, it comes in very handy when you have a case with a lot of headnotes and/or a long list of subsequent authorities. Once you choose a particular headnote, Lexis allows you to browse only that sub-set of cases if you wish. In addition, each headnote reference is hyperlinked to the portion of the citing case where the headnote is located, thus making finding subsequent references to your original authority very easy.


1 Westlaw and Lexis are registered trademarks of their respective legal research vendors. The Law Library subscribes to these products and is providing the within information through a Lunch & Learn Program to help members better utilize these services and their membership benefits. The Law Library thanks both Westlaw and Lexis for the use of their products.

2 Interestingly, not all cases reported on Westlaw have been assigned topics and key numbers. These can include both very old and very new cases.

3 Although West has launched its new product WestlawNext, the Law Library is not yet a subscriber.

4 Although Lexis has launched its new product Lexis Advance, the Law Library is not yet a subscriber.