Legal research service Fastcase has long had a citator function, called Authority Check, that lets you see how a case has been cited. Unlike Shepard’s from LexisNexis or KeyCite from Thomson Reuters, however, it has not alerted you when a case is no longer good law.

Bad Law Bot[1]

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Now it does. As of last night, Fastcase rolled out Bad Law Bot, an enhancement to its Authority Check function that identifies cases that have been reversed or overturned.

Now, when the bot identifies a case as bad law, the case will be tagged with a red flag in your search results and when you view the full case. If you run Authority Check, the report will identify the case in which the negative treatment appeared.

An important caveat here is that the identification of bad cases is being done algorithmically. Whereas Shepard’s and KeyCite use editors to analyze cases, Fastcase’s Bad Law Bot is using computer analytics. It searches for citations within cases that indicate that the cited case has been overturned or reversed. When an opinion cites a case as having been overturned, Bad Law Bot flags the case as having a negative history.

This means that Bad Law Bot will help in identifying bad law but should not be relied on as the final word on a case. As Fastcase’s own announcement says, “Because it reports what cases say in citations, researchers should rely on Bad Law Bot as an aid to identifying negative history, not as a comprehensive guide.”

Bad Law Bot in Auth Check[1]

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Fastcase CEO Edward J. Walters calls this one of the first “big data” applications for legal research, insofar as the bot has searched through some 65 million citations within the Fastcase library and harvested that data for actionable intelligence.

While Bad Law Bot is not a substitute for Shepard’s or KeyCite, it is a noteworthy enhancement for Fastcase and a further step towards the functionality of its Goliath competitors. And it’s not the last step, apparently. In a brief phone conversation with Walters last night, he described this as the “first step” in making Fastcase’s citator more comparable to Shepard’s and KeyCite. So stay tuned for further developments.

Walters has posted a video in which he explains how Bad Law Bot works. Watch the video at

Fastcase is available as a member benefit through many bar associations and also on a subscription basis.

Photo of Bob Ambrogi Bob Ambrogi

Bob is a lawyer, veteran legal journalist, and award-winning blogger and podcaster. In 2011, he was named to the inaugural Fastcase 50, honoring “the law’s smartest, most courageous innovators, techies, visionaries and leaders.” Earlier in his career, he was editor-in-chief of several legal publications, including The National Law Journal, and editorial director of ALM’s Litigation Services Division.