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Legal Research: An Overview: Search Techniques

"Big Box" v. Advanced Search

Many, if not most, commercial databases, including Westlaw, Lexis, and Bloomberg, have a main "big box" type search box and a link to take you to advanced search features.  Both search options are useful and can get you to relevant search results.  Also, the techniques discussed below for building searches and working with search results should work in the big box and in most advanced search functions.

Big box searching is helpful when you are looking for a particular source or citation.  

In addition, big box searching is useful for conducting quick searches to get a lay of the land on what might be available.  When starting your research, try searching a few key words or a key phrase.  The first set of search results are likely to include key materials discussing your topic.  For example, if you wanted to know about the tort - intentional infliction of emotional distress - under California law, you could go to Westlaw, select California as your jurisdiction, and simply type intentional infliction of emotional distress into the main search box.  Your results would look like:

If you were to read the overview results and perhaps the first few cases and secondary sources identified, you would probably get a pretty good idea of how that tort is treated pursuant to California law.

Advanced searching does offer a number of advantages.  When accessing advanced search features, both Westlaw and Lexis take you to a page that identifies the boolean search options for their databases and gives you options for building your search, such as boxes to search "all of these terms," "any of these terms," and "this exact phrase."  Accordingly, advanced search can help you get started on crafting a detailed search without the need to remember the specific terms and connectors to use. 

Moreover, databases breakdown legal documents into sub-parts or "fields."  For example, cases typically include the following fields: party name, summary, headnote, jurisdiction, and date.  Advanced search functions shows you what fields are available for the type(s) of document you are searching and allows you to search specifically within those fields.  This can be very helpful when full-text searching is getting you a lot of irrelevant search results.

Regardless of whether you search using the big box or advanced search features, after you have begun to review your search results, evaluate how relevant your results seem and adjust your search strategy as necessary.  Legal research is more art than science, and it typically takes a number of approaches for any researcher to feel that they have honed in on just what they need.

Search Builder Techniques

"And," "or," and "not" are often referred to as "Boolean connectors," named after George Boole, a mathematician whose theories serve as the underpinning for digital logic.

And.  Use "and" between your search terms to indicate that all terms must appear in your search results.  For example, the search - banana and slip and fall - will retrieve materials containing each of these terms.

Or.  Use "or" between your search terms to indicate that any one of the listed terms appear in your results.  This is very helpful when your issue may include synonyms for the same concept.  For example, the search - minor or juvenile or child or children or infant - will retrieve materials that have any one of these terms.

Not.  Use "not" to disqualify words from your search.  "Not" is a rarely used connector, but it can be helpful under certain circumstance.  For example, if you were searching for a particular anti-corruption statute, you may want to run the search - RICO not "Puerto Rico."

Proximity connectors allow you to designate how closely your search terms must appear within a document.  Common proximity connectors include:

  • /p - Terms must appear in the same paragraph. 

  • /s - Terms must appear in the same sentence.

  • /n (such as /3) -- Terms must appear within the specified number of words to each other.

For example, if you wanted to retrieve cases involving slip and fall accidents on bananas in grocery stores, you might craft the following search - (slip /s fall) /p banana /p (grocery /s store).

! is commonly used as a root expander. Words sometimes use the same "root" but have multiple endings.  For example, "treat," "treatment," and "treating" all share the same root - treat.  To search for all words that share the same root use "!" as a root expander.  For example, to search for medical malpractice claims against treating physicians, you may want to search for - malpractice /p treat! /p (doctor or physician).

Using quotation marks (" "), allows you to search for a particular phrase. To search for a specific phrase, put the phrase in quotation marks. For example, if you were interested in searching for mentions of the television show "Orange is the new Black," simply run the search "Orange is the New Black."

Parentheses - (  ) - are used to group words or phrases.  Parentheses are useful when searching for synonyms and when wanting to insure that certain concepts remain together.  For example, if your issue involves the legitimacy of a police search for a gun in the trunk of a car, you could run the search - (police! or officer) /p search /p trunk /p (auto! or car) /p (gun or pistol or firearm or rifle).

Working With Search Results

When you are viewing search results, you will see a feature just above your results labeled "sort by."  This feature allows you to see results sorted in a number of ways, including by relevance, date, and (in Westlaw and Bloomberg) by most cited.  Be mindful of how your results are sorted, as the default can vary from database-to-database and, even within the same database, based on the type of documents you are viewing.  

It is not uncommon to get more search results than is practical to review.  When this happens, you may want to consider sorting (1) by relevance, (2) by date (newest first), and (3) by most cited (if available).  For each sort, review the first fifty or so results.  This will allow you to hone in on the most relevant, the most current, and the most prominent results.

When you are viewing search results, to the left of your results, you will see options for filtering your results.  Using the available filters will allow you to narrow your search results.

Common filters are date and jurisdiction.  In addition, each different type of document will have its own unique filters.

Under the broad categories of filters, there usually are subcategories for you to choose from.  Sometimes, you will need to expand a menu or click on a link to see more options within the category/subcategory.  For example, in Westlaw, some of the secondary filters look like:

If you were to see these filters, you could click on the "+" sign next to the jurisdiction options to see all the available jurisdictions, and you would need to click on the blue link for "Publication Types" to see all the available publication types, as only a sampling of the available types are displayed.  

Explore the options available within the filters to see various ways to refine and narrow your search results.

Westlaw and Lexis both usually give you the option to "search within results."  This option typically appears at the left, along with the filters.  Searching within your results can be useful.  For example, sometimes you want to work with a broad search designed to see all that might be out there on a topic, but you would also like to see if any search results are unique to a particular context or fact pattern.  The search within results feature, like any other filter, can let you see a subset of search results without the need to adjust your original search.

Westlaw will often identify "Related Documents" to your search.  These related materials, if identified, will be displayed on the right hand side of your search results.  It can be helpful to do a quick review of these related documents to limit the risk that you are overlooking important information.

Another unique feature of Westlaw is it's "Overview" search results.  When running general searches in Westlaw that are not limited to a particular document type, Westlaw will group certain results under the heading "Overview."  These overview results are those deemed by Westlaw to provide the best context for your search terms and include a sampling of from each document type represented in the full search results.  Reviewing these overview results can be helpful to get a sense of what may be out there on your topic and to decide what document type may be most useful for your research.  After you review the overview results, select from the document types listed at the left to continue your research.