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Read It Like Opposing Counsel

Adverse Authority Is a Retrieval Problem, Not an Effort Problem

Two black holes spiral toward each other, trailing arcs of orange and blue light through a dark field of swirling gas.
Plate 61 · CollisionPlates

The case that sinks your motion isn't hiding.

You probably cited it.

Here's what nobody says out loud at the associate training: lawyers don't miss adverse authority because they didn't search hard enough. They miss it because they searched for the wrong thing. They searched for their rule. Opposing counsel is going to search for the exception to it.

Those are different searches. They return different cases. And only one of them is going to show up in the opposition.

Opinions don't wear team jerseys

We talk about cases like they pick a side. "That's a defense case." "That's a plaintiff's case." Wrong.

An opinion is a bundle of holdings. Some help you. Some help the other side. Sometimes they sit on the same page.

Exhibit A: Blank v. Kirwan. Every California demurrer cites it. The demurrer admits the material facts properly pleaded, not the contentions, deductions, or conclusions. Great for the defense. Now keep reading. Same page. When a demurrer is sustained without leave to amend, the court asks whether there's a reasonable possibility the defect can be cured by amendment. If there is, denying leave is an abuse of discretion.

That's the plaintiff's way out. Same page as your standard. You didn't cite a defense case. You cited their roadmap.

Exhibit B: Aguilar v. Atlantic Richfield. Defense lawyers love it. A defendant can win summary judgment by showing the plaintiff doesn't have, and can't reasonably get, the evidence it needs. Plaintiff's lawyers love it too. Same opinion says the defendant has to show that with evidence. Not argument. Not a paragraph pointing at the hole.

So cite Aguilar for half one, then do the thing half two prohibits, and watch opposing counsel quote your own authority back at you. In front of the judge. With a pin cite.

Direction isn't a property of a case. It's a property of a holding. Search accordingly.

The three searches that actually find the case against you

Stop typing your issue into a search bar and calling it adverse research. Attach these three searches to every rule you rely on.

1. The exceptions. Every rule has an "unless." Search for it directly. Does not apply where. Except when. Carve-out. Limited to. If you don't know the exception to your lead rule, you don't know your lead rule.

2. The cure paths. What can the other side do to fix the problem you're pointing at? Leave to amend. A Rule 56(d) declaration saying they need more discovery. A late document. A new declarant. Find out how losing parties in your posture got a second shot, because that's the second shot they're about to ask for.

3. The distinguishing cases. Pull every case that cited your lead authority and refused to apply it. Read every one. That list is opposing counsel's research memo, already written, already sitting in the citator. The flag next to "distinguished" isn't red. It doesn't need to be.

That's it. Three searches. Exceptions, cure paths, distinctions. Run them for every rule that carries weight in your brief.

Why your AI tool keeps handing you friendly cases

You typed: find cases that hurt my argument.

It handed you cases about your argument.

Here's why. "Cases that hurt me" is a stance question. Which side does this holding favor? Most retrieval is stance-blind. It finds text that looks like your query. The case holding your rule and the case holding its exception use the same words. Same facts. Same doctrine. They sit right next to each other in the math. The tool can't pull them apart unless somebody told it which way each holding cuts.

So it gives you a pile sorted by topic and calls it research. You skim the first five. They look helpful. You move on.

Ask your vendor one question: does your system know which party a holding favors, or does the model figure that out on the fly? If the answer is "the model figures it out," you have your answer.

The rule you think you know

Model Rule 3.3(a)(2). You've heard the CLE version: "disclose adverse authority." The real one is narrower. Legal authority. In the controlling jurisdiction. Known to you. Directly adverse to your client's position. Not disclosed by opposing counsel.

Narrow. And look at that word. Known.

The disclosure duty turns on what you knew. So "I never found it" is a defense to discipline.

It is not a defense to losing.

"Didn't know" keeps your license. It doesn't keep your client. And here's the part that should bother you more: the judge is going to learn about that case either way. The only question is who tells them. You, in your opening brief, framed your way, distinguished on your terms. Or the other side, in opposition, framed as the thing you hoped nobody would notice.

Judges remember who told them first.

The rule sets the floor. Strategy sets the ceiling. Aim for the ceiling.

Before you file, answer five questions

Out loud. In writing. Put the answers in the file.

  1. What's the single strongest case against me in this forum? Name it. If you can't, you haven't looked.
  2. What's the exception to my lead rule? Cite it, then explain why it doesn't apply.
  3. How do they cure? Address it before they raise it.
  4. Who distinguished my lead case? Distinguish them back.
  5. Does anything in my own string cite help them? Read every case you cited, the whole page, not the headnote.

If question five makes you nervous, good. It should.

The kicker

Your opponent is going to read your brief looking for the case you missed.

Read it that way first.

Sources: Blank v. Kirwan, 39 Cal.3d 311, 318 (1985); Aguilar v. Atlantic Richfield Co., 25 Cal.4th 826, 854 (2001); Fed. R. Civ. P. 56(d); Model Rules of Prof'l Conduct R. 3.3(a)(2).

Part 3 of 6
  1. Right Law, Wrong Stage
  2. The Case You Never Pulled
  3. Read It Like Opposing Counsel
  4. Twombly Doesn't Live Here
  5. The Docket Test
  6. Research the Carrier Won't Pay For

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Revision history

26 Jun 2026First published in the Institute library.

How to cite

Moreno, D. (2026, June 26). Read It Like Opposing Counsel: Adverse Authority Is a Retrieval Problem, Not an Effort Problem. Computational Law Institute. https://institute.legawrite.ai/articles/read-it-like-opposing-counsel

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