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Legal Research: An Overview: Validating Your Research

Why Validate Your Research?

It happens.  Cases get reversed, overruled, or superseded.  They also get criticized and distinguished.  The only way you can know if your case is still good law is to validate your research.  "Validating" your case research means to run your case through a citator service to see if there are subsequent legal authorities that invalidate your case and then reading those cases that negatively impact your case.

As discussed in more detail below, Westlaw, Lexis & Bloomberg, each have their own citator services.  Each citator service is quite good, but is important to keep in mind that these citators are fallible.  Each is only as good as its algorithm and its editors.  For most cases that you cite in your documents, it is fine to rely on one service.  However, if there is a case that truly is critical to your analysis, you would be wise to run it through a second citator service to double check that you case is good law.

To Cite or Not To Cite?: Evaluating Negative Citing References

Determining whether your case is still good law requires reviewing the citator report to see if your case was reversed, overruled, or superseded.  It is also possible that your case could be so roundly criticized or so thoroughly distinguished by other cases that you may not want to rely on it.  To determine the validity of your case, you must review those cases that offer negative treatment of your case.

There are several types of negative treatment.  Cases that have been reversed, overruled, or superseded are no longer good law and typically should not be relied upon.  However, sometimes cases are simply reversed/overruled/superseded in part, or sometimes the issue on which the case was reversed/overruled/superseded is not the issue for which you are using the case.  In those circumstances, you may decide that you can, in fact, cite to the case.  The only way to determine the extent to which you can rely upon a reversed/overruled/superseded case is to carefully READ THE CASES that indicated that your case was reversed/overruled/superseded.  There is simply no shortcut or substitute for reading those cases.  If you assume you cannot rely upon a certain case based solely on the citator report, without actually reading the negative treatment cases, you may end up losing the opportunity to cite to case that is valid for your issue and supports your position.

Other types of negative treatment include other cases distinguishing, disagreeing with, or criticizing your case.  These types of negative treatment tend to not invalidate your case, but you should still evaluate these negative treatment cases to see if they compromise your reliance on the original case.  For example, there might be a case that distinguishes your original case, and the distinguishing case is more factually similar to your issue than the original case.  In that circumstance, you probably would not want to rely on the original case.  

Accordingly, when you see references to cases that include this kind of negative treatment that does not tend to invalidate your case, you should READ THE CASES to determine the extent to which you want to rely on your original case.

Sometimes there are such a large quantity of these kinds of negative treatment cases that it impractical to read them all.  Some tips for narrowing the quantity of cases that you must read include focusing on cases:

  • from your jurisdiction,
  • from the court that issued the original case and any higher court,
  • with a significant depth of treatment, or
  • that relate to the headnotes that are the most relevant case headnotes for your issue.

Citators: Shepard's, KeyCite & BCite

KeyCite® is the citator in Westlaw.  KeyCite, quite literally, flags cases that are not good law.  Also, Key Cite provides a report of all the instances that a case has been treated negatively in other courts.

When you pull up a case in Westlaw, there are tabs that appear immediately under the case title that give you information about the case history, negative treatment by other cases, and citing references.  For all cases that you think you may rely upon, you should click on the "History" tab to review the case history.  This is important, even if there is no negative treatment (discussed below), as the case history can identify important case information, such as whether there may be an appeal pending.

This is an example of what you would see from clicking on the History tab:

If a case has negative treatment identified by Westlaw, next to the case name, Westlaw will include a red, yellow, or blue striped flag.  A red flag, as in the above sample, means a case is no longer good for at least one point of law.  A yellow flag means that a case has some negative treatment but has not been reversed or overruled.  A blue striped flag means that a case has been appealed to a U.S. Court of Appeals or to the U.S. Supreme Court.  If there is no flag, then Westlaw has not identified any negative treatment for the case.

When you pull up a case that has been flagged, in addition to the "History" tab, you also should click on the tab marked "Negative Treatment" to get the full negative history report.

The negative history report for the red flagged case identified above, looks like:

The report identifies that the case was reversed and also was distinguished by two other cases. 

While helpful, you cannot rely solely on these flags and notations to determine the extent to which you can use any given case.  As discussed in more detail in the discussion at the left regarding evaluating negative citing references, sometimes the issue on which the case was flagged is not the issue for which you are using the case.  The only way to determine the extent to which you can rely upon a case with negative treatment is to carefully READ THE CASES that treat your case negatively.

For more information on using KeyCite, see the Westlaw User Guide for Checking Citations in KeyCite and other tutorials available from the Westlaw Training & Support Center.

Shepard's® is the citator in Lexis.  Shepard's indicates when cases are no longer good law.  Also, Shepard's identifies instances when a case has been treated negatively by other cases.

When you pull up a case in Lexis, there are indicators that appear next to the case name to signal if the case is good law.  A red stop sign indicates that a case may have been overruled or reversed.  An orange box with the letter "Q" inside means that the validity of a case may be in question, such as when a case is superseded.  A yellow triangle means that a case has other negative treatment such a being distinguished, limited, or criticized.  For more information about these and other signals, see the Lexis Advance Help Guide on Shepard's Signal ™ Indicators.

This is an example of what a red stop sign case looks like:

To the right of the case name, as can be seen above, there is a box marked "Shepard's®" with certain summary information about negative case treatment and other citing references.  You should always click on the link to "Shepardize® the document" to see the full Shepard's report of case history, negative treatment, and other citing references.

When you access the full Shepard's Report, you will see separate tabs on the left to view the case history, citing cases, other citing sources, and other available information.  It is recommended that you at least skim each of these for cases you intend on using.

If you pull up the Shepard's report for the above case, and click on "Appellate History," you would see:

To see all citing cases, including other negative treatment cases identified by Lexis, you must click on "Citing Decisions."  That generates a list of all the cases, identified by Lexis, that have cited to your case.  At the left of that list is a series of filters that will allow you to narrow the results.  The filters include "Analysis," which allows you to view the negative treatment cases only.

For example, if you clicked on "Citing Decisions" for the above case, and then selected "Questioned", under the "Analysis" menu, you would see:

While helpful, you cannot rely solely on these indicators and notations to determine the extent to which you can use any given case.  As discussed in more detail in the discussion at the left regarding evaluating negative citing references, sometimes the issue on which the case was treated negatively is not the issue for which you are using the case.  The only way to determine the extent to which you can rely upon a case with negative treatment is to carefully READ THE CASES that treat your case negatively.

For more information on using Shepard's, see the Lexis Help page "Using the Shepard's® Citation Service."

BCite is the citator in Bloomberg.  BCite indicates when cases are no longer good law. Also, BCite identifies instances when a case has been treated negatively by other cases.

When you pull up a case in Bloomberg, there are indicators, referred to as "operators," that appear next to the case name.  A red box with a minus sign in it indicates that the case has been overruled in full or in part.  An orange box with a circle in it indicates that the case has been superseded by statute.  A yellow box with a triangle in it indicates that the case has been criticized.  A blue box with a slash in it indicates that the case has been distinguished.  For more information about these and other operators, see Bloomberg Law Citator, BCite Operators.

This is an example of what a red box case looks like:

To the right of the case name, as can be seen above, there is a column with three icons, the middle of which is "BCite Analysis." Clicking on that icon will open up a column with BCite information, allowing you to review case history, negative case analysis, and other information.  The BCite column looks like:

Use the links provided in this column to navigate to a list of the cases identified by Bloomberg for each category.  When you access the case lists, you will see a series of filters on the left of the list that will allow you to narrow the results.

For example, to see the cases that distinguish the above case, click on the link "Distinguished" to see:

While helpful, you cannot rely solely on these operators and notations to determine the extent to which you can use any given case.  As discussed in more detail in the discussion at the left regarding evaluating negative citing references, sometimes the issue on which the case was treated negatively is not the issue for which you are using the case.  The only way to determine the extent to which you can rely upon a case with negative treatment is to carefully READ THE CASES that treat your case negatively.

For more information on using BCite, see the Bloomberg Law Product Help page for BCite.