The Citation Code

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.

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.

A citation becomes easier to build when each component has a job. A volume selects a publication sequence. A first page identifies a report. A pinpoint locates the passage that supports the sentence. A signal explains how the passage relates to the claim. Once those jobs are clear, unfamiliar citations become problems you can reason through.

The first chapter starts with one case and one sentence. Later chapters add placement, signals, quotations, short forms, and source-specific conventions. The editing chapters bring those decisions together in a document. The capstone supplies an entire fictional source packet so you can check the work yourself. Advanced chapters apply the same care to different legal and publication systems.

The exercises ask for decisions as well as finished citations. An answer can look plausible while using the wrong edition, attributing a dissent to the court, or directing the reader to a page that does not support the sentence. The answer key explains where those decisions arise and what information resolves them.

The reference section identifies its source and coverage so an abbreviated selection is not mistaken for a complete current directory. When a source or receiving instruction leaves a question open, preserve that question and find the missing information before relying on the citation.

Read the opening problem and objectives, then inspect the annotated model. Work through the explanations and editing decisions before trying the exercises. Compare your reasoning with the answer key as carefully as you compare punctuation. Acceptable alternatives depend on the supplied facts and applicable instructions.

Every exercise has a stable identifier, such as CC-04-05. The first number identifies its chapter; the second identifies the exercise. The answer key uses the same identifier. Chapter 18 contains a cumulative memorandum exercise with all necessary fictional authorities and record excerpts.

Invented sources are labeled “Fictional training example — not legal authority.” Their facts exist for practice. Real examples have source records describing the material actually inspected. Compact chapter notes identify useful sources; detailed editorial records accompany the production project.

Use the receiving court, publication, instructor, or assignment's instructions when they differ from a general convention. Keep source identity, substantive support, and formatting as separate checks. None can substitute for the others.

The contents and index provide chapter and section destinations. The digital edition includes internal links; the print edition preserves visible references and paginated contents. Reference tables repeat column headings when they continue across pages.

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.