An independent, practice-first citation handbook.

The Citation Code teaches how to identify a legal source, build a citation, locate the supporting passage, and check the citation in its document. Its core covers United States memoranda, briefs, filings, and comparable legal writing. Advanced chapters extend the method to academic editing, foreign and international sources, Tribal Nations, archives, and emerging media.

Different source systems remain distinct. An international instrument is not a United States statute, a Tribal Nation's court is not a state court, and an academic journal's footnote conventions do not automatically govern a brief. Specialized chapters explain both the components to collect and the receiving authority's instructions to consult.

A formatted citation identifies a source. The source's text must also support the proposition, and its legal force must fit the argument. Historical decisions demonstrate inspected passages; their inclusion does not represent a review of every subsequent citing decision. Source notes identify relevant conventions, official materials, and verification boundaries.

Indigo 2.0 supplies the general practitioner baseline. Differences observed in other citation systems are identified where they matter. Explicit house choices resolve presentation questions without pretending that every court or journal requires the same answer. Local and source-specific requirements take precedence in the documents to which they apply.

This handbook adapts citation conventions and selected reference information from The Indigo Book: A Manual of Legal Citation (Christopher Sprigman & Jennifer Romig et al. eds., Public.Resource.Org 2d ed. 2021). Its manifest dedicates its contributors' work to the public domain under CC0. The covered material may be reused commercially. No exclusive ownership of that material is claimed here, and its dedication does not automatically apply to separate contributions to this handbook.

Indigo's manifest states a final release of August 31, 2022, while prescribing a bibliographic citation with 2021. Both statements are preserved. The complete source snapshot used here was retrieved October 8, 2026 UTC.

Licensed Bluebook Online materials were consulted to compare conventions and identify topics requiring fuller treatment. This handbook uses original explanations and exercises. It does not reproduce Bluebook instructional text or tables. Rights in separately protected third-party publications remain with their respective holders; a citation or link is not permission to reproduce their contents.

This book is authored by Matthew D. Giron. It is not sponsored, endorsed, or approved by The Bluebook's publishers, The Indigo Book's editors, Public.Resource.Org, any court, or any educational institution. Acknowledgments do not imply participation in preparing this handbook.

This book credits Public.Resource.Org, Inc., and the editors and contributors to The Indigo Book. Its second-edition acknowledgment names Jennifer Murphy Romig and assistance from Annabelle Bichler, Nancy Jin, Akhil Morissetti, and Daniel Kaltman. Its first-edition work was led by Christopher Jon Sprigman with New York University School of Law students. The complete acknowledgments remain in the preserved source snapshot.

The source also thanks Mindy Goldstein, Mark T. Gray, Mike Lissner, Amber Madole, Olivia Marbutt, Sue Payne, Robin Pederson, Blake Reid, Heather Simmons, Allison Thornton, David Ziff, Jeannette Livingston, Ben Chapman, Zach Stevenson, Frank Bennett, Carl Malamud, and Laura Romig. These names report Indigo's acknowledgments.

CourtListener supplied case-identification results and opinion passages. Official courts, legislatures, agencies, archives, and international institutions supplied public materials identified in the chapter notes. The source records distinguish inspected text, bibliographic information, source conventions, and editorial choices.

citationcode.com is the online edition of the book. Content is imported from the author's production manuscript and rebuilt as a static site, so what you read here is the same text as the print and PDF editions. The current content snapshot was imported on October 8, 2026.

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Nothing here is legal advice. A citation that is formatted correctly can still point to a source that does not support a sentence or that is no longer good law. Local and receiving-court requirements control. Read the how to use section before relying on any model.