The Caselaw Access Project offers free, public access to over 6.5 million decisions published by state and federal courts throughout American history. Because our mission is providing access to legal information, we make these decisions available in a variety of formats through a variety of different access methods.

One type of access we’ve been working hard on recently is our search interface, which you can get to at We’ve had basic search working for a while, and we’re pleased to share our new advanced search filters.

Advanced filters work exactly as you’d expect. Start your search with keywords or phrases, and then use the filters to narrow down jurisdictions, courts, and dates. Say you’re looking for Massachusetts cases from 1820 to 1840 that contain the word “whaling.”

Search for cases that include the word "whaling" decided from 1820 to 1840 in Massachusetts, showing advanced filters for full-text search, date from, date to, case name abbreviation, docket number, reporter, jurisdiction, citation, and court.

You can also access the advanced filters from the search results screen, so that you can fine-tune your search if you’re not happy with the initial results. Delete or modify any of the filters as you go, and sort the results chronologically or by relevance.

Search results for cases that include the word "whaling" decided from 1820 to 1840 in Massachusetts, showing filters on left.

There is a lot more we hope to do with search, but we hope you enjoy this improvement. If you have ideas of your own, please share them with us at

CAP is a project of the Library Innovation Lab at Harvard Law School Library. We make open source software that helps people access legal information, preserve web sources with, and create open educational resources with H2O.