As former litigators, we always feared that when attorneys miss precedents, the stakes are high. And we had a pretty good idea — anecdotally — that lawyers might be missing more cases than they think. We wanted to get a clearer picture of how often it’s happening, and what the implications really are, from the people whose opinion matters most: judges.

Our research uncovered that judges have a surprisingly consistent opinion of the work they see from us litigators: they believe attorneys miss important cases often, and when they do, it has real consequences in the course of litigation, as discussed in the recent Above the Law column, “You’re Bad at Legal Research, And Your Judge Knows It.”

In fact, our survey of over 100 federal and state judges revealed some pretty shocking statistics. First, every single judge we surveyed said that they or their clerks have discovered relevant precedent that the parties before them missed. Over a quarter of judges (27%) said that they or their clerks catch missing precedent the attorneys should have cited “most of the time” or “almost always.” The vast majority of judges (83%) say that they see this problem at least some of the time. A small minority (16%) say they rarely, but still sometimes, catch missing cases that litigators should have cited in their submissions.

More importantly, there are real implications of attorneys missing precedents. More than two-thirds of judges surveyed said that attorneys missing cases before them has materially impacted the outcome of a motion or proceeding. That’s a huge and troubling number.

A few judges expanded on the issue of missing cases in written responses to us. A judge in the Southern District of New York recounted a criminal case where the government attorneys missed a critical controlling case in an evidentiary issue, which ended up being the dispositive precedent in the motion, which controlled the outcome in the case and ultimately led to acquittal. The judge and his clerks found the key case themselves the night before motion in limine arguments, and the government was unable to distinguish it at that stage. “Even excellent lawyers miss things, and sometimes it materially impacts the outcome,” said the judge.

All told, according to the judiciary, attorneys — even good attorneys — aren’t as good at legal research as we might think. Lawyers have long relied on legacy research tools alone — and pay a lot of money for those subscriptions — but attorneys leveraging those tools are still missing cases.

The good news is attorneys are turning to new technologies like A.I. to help. We all know on some level that we could be doing it better. Strong technology can get us there.

Read our full report, “The Prevalence of Missing Precedents.”