What the Harvey Agent Changes About Legal Research
Harvey helps lawyers find the cases that matter, understand how they relate, and apply that authority to their own work.
It's 11pm. You have a hundred and forty tabs open. You've read enough district court and appellate opinions that you could recite the doctrine by heart. You just need one court that agrees with your position. Most of what you're reviewing will not end up in the brief. You read more decisions anyway, because the only way to know which cases matter is to go through the ones that don't.
This is not busywork. Somebody has to explain the subtle distinctions that your client trusts you to catch — like the Northern District of Illinois applying a slightly different interpretation of the relevant issue than the Eastern District of California. Reading, understanding, interpreting, and mastering the relationships between cases is at the heart of professional legal research. But before you can develop mastery, you need to simply find the cases that matter.
Agents That Help you Build Mastery
This is where Harvey steps in. Harvey extracts the relationships across its entire case law corpus — which cases cite which, how they’re treated, where a nuanced line of reasoning holds and where it breaks – and makes them available to the agent as it works. So when you submit a query, the Harvey agent can pursue those connections itself, moving through the relationships between opinions before responding to your issue.
All of this work is in service of the lawyer’s own mastery over the case law. The Harvey agent iterates behind-the-scenes: retrieving authority, following relevant citations and distinctions, checking its work against the prompt, and returning grounded answers with inline citations. The agent reveals the shape of the authority on the issue, providing lawyers with a map for deeper understanding and professional expertise. The lawyer can focus on the harder part, like challenging the scope of holdings, finding key distinctions, or working out whether a case is actually fatal. This is deliberate cognitive work: mastery, not retrieval.
US Case Law in Harvey
We made Harvey’s US Case Law knowledge source available to customers in June, so research, analysis, and drafting could happen in one platform. Harvey’s US Case Law comprises millions of opinions across the entire federal judiciary and all 50 states – with coverage for over 2,100 federal and state courts, including more than 8 million published opinions along with scanned reporter copies. It includes comprehensive reported case law for all federal and state jurisdictions alongside unpublished decisions.
Harvey has also spent months indexing, extracting, and substantively enriching each opinion. The Harvey agent can now search by publication status, date filed, court, citing references, and cited by references. The agent can review Bluebook citations and isolate specific page breaks from reporters. All of this work results in more accurate, insightful, and valuable research outputs for US Case Law queries.
Harvey will continue adding to and enriching its US Case Law corpus, with greater coverage for unpublished decisions and state trial court orders in the coming weeks. US Case Law will expand even further as Harvey invests in gathering and digitizing more case law.
Mastery in Practice
The real measure of value for Harvey’s investment in US Case Law is whether lawyers continue to use and trust it. And in the span of a few weeks, US Case Law has quickly become one of our most popular knowledge sources on the platform. Users have more than doubled every month since our release in June. With increasing week-over-week growth and new records set each day, the Harvey agent performs cutting edge research in support of lawyers’ needs — from high-stakes filings to research emails.
Most importantly, lawyers do things with US Case Law. They attach documents to US Case Law queries at twice the rate of other sources, run more deep research tasks, query it more frequently in the Harvey for Word add-in, and click on citations more than twice as often as other sources. Harvey’s US Case Law allows users to accomplish more substantive work, reducing their time to mastery.
Lawyers can query about circuit splits and their impact on the fact pattern in their own filings. They can hand Harvey opposing counsel’s motion in limine and ask what authorities they rely on and the strongest cases in response. They can query US Case Law right inside the brief they’re drafting, through the Harvey for Word add-in, without leaving the document. For every answer, citations come back rendered inline, so the partner reviewing the argument can immediately read the relevant passage next to the claim.
These aren’t just hypothetical use cases. Lawyers are already performing all of these actions and more with US Case Law within Harvey. In the coming months, we expect US Case Law to become even more deeply embedded in lawyers’ daily routines, always decreasing their time to mastery.
What We’re Building Next
Lawyers are bringing substantive legal questions to Harvey’s US Case Law, attaching documents and context at a significantly higher rate than other knowledge sources. That’s why we’re investing even more here in the next quarter, with dedicated teams across Product, Engineering, AI Research, Data, Legal Engineering, and more.
Three pieces are underway. First, deeper classification to understand the structure of opinions. Lawyers ask complex questions, and the Harvey agent needs to know how key features relate to one another: which court, which judge, what procedural posture, scope of the disposition, subsequent history, and more. All of these elements will feed into the Harvey agent’s retrieval and analysis. So the agent knows that there’s a supporting proposition for your argument but the relevant court ultimately ruled the other way, and the agent is intelligent enough to flag these crucial nuances.
The second is precedential treatment: a warning on a case when the court’s opinion was ultimately overturned on appeal. But not a static warning that was pre-computed before your issue was even possible, meaning treatment removed from your specific facts and issues. Hard cases exist because of interpretive ambiguity, and precedential status is rarely binary for the issues that matter. So the Harvey agent will check at runtime whether the specific claim that you want to make remains viable, even amidst overturned, abrogated, questioned, or ambiguous language.
And the third is the brief itself: hand Harvey a finished draft to check every citation against its opinion. Features like “does the case exist” or “is the quote accurate” are just the beginning. Harvey will also explain whether the introductory signal is appropriate (see and but see are worlds apart), how the parenthetical’s description lines up with the case’s holding, and whether other cases tend to be cited alongside the one you chose. The Harvey agent will perform all of these actions and more — always in the interest of allowing you, the reviewing lawyer, to master the cases at hand.
We’ll be announcing more details at the Chicago Harvey FORUM in November.
