How to Shepardize a Case: Checking If a Case Is Still Good Law

To Shepardize a case means to run it through a citator to see how later courts have treated it, so you can confirm it is still good law and has not been overruled, reversed, or seriously undermined. You do it with a citator service such as Shepard's on LexisNexis or KeyCite on Westlaw, and you read the treatment signals it reports before you rely on the case.

The verb "to Shepardize" comes from Shepard's Citations, the citator that made this check routine long before computers. Today the concept is the same whether you use Shepard's, KeyCite, or a free citing-references tool: never rely on a case until you have confirmed later courts have not knocked it down.

What it means to Shepardize a case

When a court decides a case, that decision does not sit frozen in time. Later courts cite it, and when they do they may follow it, distinguish it, criticize it, limit it, or overrule it. Shepardizing is the process of pulling up that citing history so you can see the full picture. A citator is the tool that compiles every subsequent case, statute, and secondary source that has referenced your case, and labels how each one treated it.

This is the last and most important step of any research project. You can find a perfectly on-point case, read its holding, and build an argument around it, only to discover it was overruled two years later. Shepardizing prevents that embarrassment, and worse.

Shepard's versus KeyCite

The two dominant commercial citators are Shepard's (on LexisNexis) and KeyCite (on Westlaw). They do the same job with different branding, and we compare them head to head in KeyCite vs Shepard's:

• Shepard's uses colored signals. A red stop-sign icon warns of strong negative treatment such as overruling or reversal. A yellow triangle flags caution, like a decision that has been questioned or limited. A green diamond indicates positive or neutral treatment.
• KeyCite uses flags. A red flag means the case is no longer good law for at least one point. A yellow flag means there is some negative treatment worth reviewing. Other indicators show related history and citing references.

Both let you filter citing references by treatment, jurisdiction, and depth, so you can go straight to the cases that criticized or overruled yours. We compare the two platforms more broadly in Westlaw vs LexisNexis.

How to Shepardize a case, step by step

1. Pull up the case in your citator of choice and look at the top-level signal or flag. That icon is a summary, not the answer.
2. Read the negative treatment first. Filter the citing references to show negative treatment and read those cases. A red signal usually means "overruled" or "reversed," but you need to see what point was affected, because a case can be bad law on one issue and perfectly good on another.
3. Confirm the negative treatment touches your issue. If a case was overruled on a procedural point but you are relying on it for a different holding, it may still support you. This is why you read, rather than just glance at the color.
4. Check the jurisdiction. Negative treatment from a court that does not bind yours is a caution, not a death sentence. Treatment from a higher court in your jurisdiction is decisive.
5. Look for positive and explaining cases that reaffirm or apply your case, which strengthen your reliance.
6. Record the date you checked. Good law today is not guaranteed good law next month. Note when you verified.

How to check if a case is still good law without a paid citator

Before you assume you need to buy one, it is worth seeing what every citator option costs side by side, including the one a great many state bars already include in your dues.

You do not need a commercial subscription to do a reasonable good-law check, though the free approach takes more manual reading:

• Google Scholar shows "How cited" and lists cases that cite your decision. Read the recent ones, especially any that reverse or overrule.
• CourtListener offers a citation tool and citing-references view that flags subsequent treatment.
• Read forward manually. Even without any tool, following the cases that cite yours and reading how they describe it is the essence of the check.

The tradeoff is that free tools may not neatly label every treatment the way a commercial citator does, so you carry more of the reading burden yourself. If you rely on free sources, be especially careful, and cross-check anything important. The underlying skill of finding citing cases is covered in how to find case law.

Reading the signals without over-trusting them

A colored signal is a helpful headline, but it is generated by an editorial process and it is not a substitute for reading. A green light does not guarantee your case fits your facts, and a yellow flag does not automatically disqualify a case. Treat the signal as a prompt to investigate, then read the actual treating cases and decide for yourself whether the treatment affects the point you are relying on.

This is the same discipline that separates careful research from careless research, which we lay out in how to research case law.

Why the good-law check matters more than ever

Two trends make Shepardizing more important, not less. First, the volume of decisions keeps growing, so the odds that some later case touched yours are high. Second, AI research tools can produce citations that look authoritative but are outdated or, in the worst case, entirely fabricated. We explain the fabrication problem in AI hallucination in legal cases.

The good-law check is your safety net. It confirms the case exists, confirms it still stands, and confirms it stands for the point you are citing. That is why Cases pairs each result with a checkable citation that links to the source, so confirming and then Shepardizing is a natural next step rather than a chore.

Understanding negative treatment

"Negative treatment" is a spectrum, not a single verdict. Knowing the gradations helps you read a citator intelligently:

• Overruled. A higher court has rejected the case's rule outright. This is the strongest negative treatment, and it usually means the case is no longer good law for that point.
• Reversed or vacated. The decision itself was undone on appeal. A reversed trial decision no longer stands.
• Superseded by statute. A legislature changed the law, so the case's interpretation no longer applies even though no court overruled it.
• Criticized or questioned. Later courts disagreed with the reasoning without overruling it. The case may still be good law but stands on shakier ground.
• Limited or distinguished. Later courts narrowed the case or set it apart on the facts. It may still control in its original context.

The practical lesson is that a warning icon is a starting point. You must read the treating case to learn which flavor of negative treatment applies and whether it touches the point you care about.

Good law on one point, bad law on another

One of the most important nuances is that a case can be split. A decision might be overruled on a procedural holding while its substantive holding remains perfectly good law, or vice versa. A citator flag summarizes the case as a whole, but your reliance is usually on a specific point. This is why the disciplined approach is to identify exactly which holding you are relying on, then check whether any negative treatment reaches that holding. Treating a red flag as a blanket disqualification can cause you to abandon a case that still fully supports you, while treating a green light as blanket approval can lull you into relying on a point that was quietly limited.

A good-law checklist

1. Run the case through a citator or a citing-references tool.
2. Read the negative treatment before anything else.
3. Confirm any negative treatment actually affects your point.
4. Weigh the treating court's jurisdiction and level.
5. Note the date you verified.
6. Re-check before you file or rely on the research again.

When to Shepardize, and how often

Timing matters as much as method. Run a good-law check on any case before you rely on it in a memo, brief, or advice, and run it again just before you file, because treatment can change between drafting and filing. For an important matter that stays open over weeks or months, re-check the key cases periodically, since a decision that was good law when you started could be overruled while the matter is pending. The habit to build is simple: never let a citation leave your hands, into a filing or into advice, without a fresh confirmation that it still stands. The few minutes this takes are trivial compared to the cost of relying on a case that has quietly become bad law.

The honest boundary

A good-law check reduces risk, but it does not turn research into advice, and no citator is infallible. AI-assisted tools, including Cases, are for informational research only, not legal advice. Always read the treating cases and verify the citation at its source. Shepardizing tells you whether a case still stands; your judgment tells you whether it helps your situation.

Key takeaways

• Shepardizing means checking how later courts treated a case so you can confirm it is still good law.
• Shepard's uses colored signals; KeyCite uses flags; both point you to negative treatment.
• Read the treating cases, do not just trust the color, and confirm the treatment touches your issue.
• Free tools like Google Scholar and CourtListener support a manual good-law check.
• Always verify a case exists, still stands, and stands for your point before relying on it.