6.1 Bluebook citation system

Overview of Bluebook Citation

The Bluebook citation system is the standard format for citing legal authorities in the United States. It gives legal professionals a shared language for referencing cases, statutes, and other sources so that any reader can quickly locate and verify the material. If you're in a Legal Method and Writing course, you'll use it constantly.

Purpose and Importance

Citations do more than just give credit. They let readers track down your sources, check your reasoning, and evaluate the strength of your arguments. Proper Bluebook citation also signals professionalism and academic integrity. Courts, law reviews, and practitioners all rely on it as a baseline standard.

Structure and Organization

The Bluebook is divided into two main parts:

• Bluepages (sometimes called "Blue Pages"): Simplified rules designed for practitioner documents like briefs and memos.
• White Pages: More detailed rules for academic legal writing, such as law review articles.

Beyond that division, the Bluebook contains 21 rules covering citation formats for different types of legal authorities, plus a set of tables with abbreviations for court names, reporters, jurisdictions, and more. When you're unsure how to cite something, the tables are often where you'll find your answer.

Citation Formats

Citation format depends on the type of source you're citing. A case citation looks different from a statute citation, which looks different from a law review article citation. But most citations share common elements: author or party names, a volume or title number, an abbreviation for the source, a page or section number, and a date.

The Bluepages and White Pages also differ in formatting conventions (for example, italics vs. underlining for case names), so always confirm which set of rules applies to the document you're writing.

General Citation Rules

These are the foundational principles that apply across all source types. Getting these right makes everything else easier.

Full Citation vs. Short Form

The first time you cite a source, give the full citation with all required elements. After that, you can use a short form to avoid repeating the entire citation.

• Id. refers to the immediately preceding cited source. If you cite the same source twice in a row, use Id. (with a period, italicized). Add a pinpoint page if you're referencing a different page: Id. at 485.
• Supra refers back to a source you cited earlier but not immediately before. It's used for secondary sources (books, articles), not for cases or statutes.
• For cases cited earlier, use a shortened form with one party name, the volume, reporter, and "at" plus the pinpoint page.

Typeface Conventions

Typeface rules differ between academic writing and practitioner documents:

• Academic writing (White Pages): Case names are italicized. Book titles and certain other elements appear in large and small capitals.
• Practitioner documents (Bluepages): Case names are underlined (or italicized, depending on local preference). Large and small capitals are generally not used.
• Most other citation elements (reporter names, volume numbers, dates) appear in regular roman type.

Spacing and Punctuation

• Use a single space between elements within a citation.
• Periods separate major citation components, but a period does not appear right before a parenthetical.
• Commas separate multiple authorities cited under the same signal.
• Semicolons separate citations to different authorities in a citation string.

These details seem minor, but inconsistent spacing and punctuation are among the most common errors flagged in legal writing.

Case Law Citations

Case citations are the most frequently used citation type in legal writing. Getting the format right is non-negotiable.

Basic Case Citation Format

The standard format is:

For example: Brown v. Board of Education, 347 U.S. 483 (1954).

Here's what each element represents:

1. Party names in italics (academic) or underlined (practitioner), separated by "v."
2. Volume number of the reporter
3. Reporter abbreviation (e.g., U.S., F.3d, S. Ct.)
4. First page where the case begins
5. Court and year in parentheses

For a pinpoint citation (citing a specific page), add the page number after the first page: Brown v. Board of Education, 347 U.S. 483, 495 (1954). The pinpoint page is where the specific language or holding you're referencing appears.

Note: When citing U.S. Supreme Court cases from the United States Reports (U.S.), you don't include the court name in the parenthetical because the reporter itself identifies the court.

Parallel Citations

Some cases appear in more than one reporter. A parallel citation provides the additional reporter reference. This is most common with state court cases, where you might cite both the official state reporter and a regional reporter.

The format places the primary citation first, followed by the parallel citation. Check Bluebook Table T1 for your jurisdiction's requirements, since some courts require parallel citations and others don't.

Subsequent History

If a case was later affirmed, reversed, or had certiorari denied, you include that information after the main citation, separated by a comma.

Common abbreviations:

• aff'd = affirmed
• rev'd = reversed
• cert. denied = certiorari denied

Example: Smith v. Jones, 500 F.3d 200 (2d Cir. 2007), aff'd, 555 U.S. 100 (2009).

You can omit subsequent history that doesn't affect the case's weight or relevance, such as a denial of rehearing.

Statutory Citations

Statutes require a different citation format than cases. The key is knowing which code to cite and how to format the reference.

Federal Statutes

The United States Code (U.S.C.) is the official codification of federal statutes and the preferred source for citation.

Example: 42 U.S.C. § 1983 (2018).

1. Start with the title number of the U.S. Code.
2. Add the abbreviation U.S.C.
3. Use the section symbol § followed by the section number.
4. In parentheses, include the year of the code edition or supplement you consulted.

If the official U.S.C. is unavailable, you can cite the unofficial codes: United States Code Annotated (U.S.C.A.) or United States Code Service (U.S.C.S.), including the publisher in the parenthetical.

State Statutes

State statute citation formats vary by jurisdiction, but they generally follow a similar pattern: code name, section number, and year.

Example: Cal. Penal Code § 422 (West 2019).

Always consult Bluebook Table T1 for the specific abbreviation and format required for each state's code. Some states use title and section numbers (like the federal code), while others use named codes.

Session Laws

Session laws are newly enacted statutes that haven't yet been incorporated into the codified code. You cite them when dealing with very recent legislation or conducting historical research.

The citation includes the public law number and the Statutes at Large reference, which is the official chronological compilation of federal laws.

Secondary Source Citations

Secondary sources support your arguments but don't carry the same authority as cases or statutes. Proper citation still matters because it lets readers evaluate and locate your supporting material.

Books and Treatises

Example: Richard A. Posner, Economic Analysis of Law 237 (9th ed. 2014).

Include a pinpoint page or section number so readers can find the specific passage. For institutional authors (like the American Bar Association), list the institution where the author name would go.

Law Review Articles

Example: Cass R. Sunstein, Beyond the Precautionary Principle, 151 U. Pa. L. Rev. 1003, 1018 (2003).

Journal names are abbreviated using the abbreviations found in Bluebook Table T13. The article title is italicized in academic citations.

Newspapers and Magazines

Example: Adam Liptak, Supreme Court Tie Blocks Obama Immigration Plan, N.Y. Times, June 23, 2016, at A1.

For online-only articles with no print equivalent, include the URL and the date you last accessed the page.

Electronic Source Citations

Digital sources are increasingly common in legal research. The Bluebook's rules for electronic citations continue to evolve, but the core principle is straightforward: provide enough information for the reader to find the source.

Internet Sources

Include as much identifying information as possible: author, title, source, date, and URL.

One practical tip: use Perma.cc links when possible. Perma.cc archives web pages so that even if the original page is taken down or changed, your cited version remains accessible. For sources that update frequently, include the date and time of access.

Electronic Databases

When a source is available in print, cite the print version. Add a database reference only when the source is unavailable in print or when the database version is the only one you accessed.

The format mirrors the print citation with the database identifier appended. Example: United States v. Jones, 565 U.S. 400 (2012), available at 2012 WL 171117.

The specific format depends on the database (Westlaw, LexisNexis, Bloomberg Law), so check the Bluebook's rules for each.

Social Media

Social media posts can be cited when relevant, though you should consider the permanence and reliability of the source.

Example: @POTUS, Twitter (Jan. 20, 2021, 12:00 PM), https://twitter.com/POTUS/status/1351931465943891970.

Include the exact date and time of the post, since social media content can be deleted or edited.

Signals and Introductory Phrases

Signals tell your reader how a cited authority relates to the point you're making. Using the wrong signal (or no signal at all) can misrepresent the strength of your argument.

Common Signals

• [No signal]: The cited authority directly states the proposition. This is the strongest form of support.
• See: The authority supports the proposition, but the connection requires an inferential step rather than a direct statement.
• See, e.g.,: Multiple authorities support the proposition; the cited source is just one example.
• Cf.: The cited authority supports the proposition by analogy or comparison.
• But see: The authority directly contradicts the proposition.
• See generally: The authority provides helpful background on the topic.

Choosing the right signal is a judgment call, but the key distinction is between no signal (direct support) and see (indirect support). Mixing these up is a common mistake.

Explanatory Parentheticals

Parentheticals appear after the citation and briefly explain the relevance of the source. They typically begin with a present participle (e.g., holding, explaining, noting).

Example: Smith v. Jones, 123 F.3d 456, 789 (9th Cir. 1997) (holding that the Fourth Amendment applies to digital searches).

Keep parentheticals concise. They should give the reader just enough context to understand why you cited the source without having to look it up.

Order of Authorities

When citing multiple authorities under the same signal, arrange them in this order:

1. Constitutions
2. Statutes
3. Cases (federal before state, higher courts before lower courts)
4. Secondary sources

Within each category, list sources in reverse chronological order (most recent first) unless one source is clearly more authoritative. Separate different groups of authorities with semicolons.

Quotations and Alterations

Direct quotations require careful formatting. The Bluebook has specific rules to ensure that quoted material is presented accurately and that any changes are transparent.

Block Quotes

Use a block quote for quotations of 50 words or more.

• Indent the entire block on both left and right margins.
• Single-space the block quote text.
• Do not use quotation marks around the block.
• Place the citation on a new line after the final punctuation of the block quote.
• Introduce the block quote with a colon, unless the quoted language flows grammatically into your sentence.

For quotations under 50 words, keep them inline with quotation marks.

Omissions and Ellipses

When you cut material from within a quotation, use an ellipsis to show the omission:

• Three periods (. . .) for omissions within a single sentence. Note that each period is separated by a space.
• Four periods (. . . .) for omissions that span the end of one sentence and the beginning of another. The first period functions as the sentence-ending period.
• You do not need an ellipsis at the beginning or end of a quotation, since readers understand you're excerpting from a larger text.

The most important rule: never omit material in a way that changes the meaning of the original text.

Alterations and Brackets

Brackets indicate any change you've made to the original quoted text:

• [Capitalization changes]: If you change the first letter of a quote to uppercase or lowercase to fit your sentence, put that letter in brackets.
• [Additions]: If you add a word for clarity, bracket it.
• [sic]: Place this after an error that exists in the original text to show the mistake isn't yours.
• For significant alterations, explain the change in a parenthetical after the citation (e.g., "(emphasis added)" or "(alteration in original)").

Tables and Abbreviations

The Bluebook's tables are your reference for standardized abbreviations. You'll consult them constantly, so it's worth knowing where to find what you need.

Court Name Abbreviations

Found in Bluebook Table T7. Use these abbreviations in the parenthetical portion of case citations.

• "S. Ct." for Supreme Court (when citing the Supreme Court Reporter)
• "9th Cir." for the Ninth Circuit Court of Appeals
• "S.D.N.Y." for the Southern District of New York

Spell out court names in full when they appear in the text of your sentence rather than in a citation.

Reporter Abbreviations

Found in Table T1 (federal) and state-specific entries within T1.

• "U.S." for United States Reports
• "F.3d" for Federal Reporter, Third Series
• "S. Ct." for Supreme Court Reporter

Always include a space between the volume number and the reporter abbreviation.

Jurisdiction Abbreviations

Found in Bluebook Table T6 (for state abbreviations used in citations).

• "Cal." for California
• "N.Y." for New York
• "Tex." for Texas

These abbreviations appear in the parenthetical of case citations and in statutory references. They don't always match postal abbreviations (e.g., "Cal." not "CA").

Bluebook vs. Other Citation Systems

The Bluebook is dominant, but it's not the only legal citation system. Knowing the alternatives helps you adapt to different practice settings.

ALWD Citation Manual

The ALWD Guide to Legal Citation (published by the Association of Legal Writing Directors) is an alternative used by some law schools and practitioners. It covers the same types of sources as the Bluebook and follows a similar structure, but it was designed to be more accessible and practice-oriented.

Many of the citation formats are identical or nearly identical between the two systems. The differences tend to be in specific formatting details. If your school or jurisdiction uses ALWD, the transition from Bluebook knowledge is relatively smooth.

Local Citation Rules

This is where things get jurisdiction-specific. Many state courts and some federal courts have their own citation rules that override or supplement the Bluebook.

• State courts may require parallel citations that the Bluebook doesn't.
• Some jurisdictions have their own style manuals (e.g., the California Style Manual, the New York Law Reports Style Manual).
• Federal courts may have local rules specifying citation preferences.

Before filing any document, always check the applicable court's local rules. Getting the citation format wrong in a brief can undermine your credibility with the judge.

Common Citation Errors

Knowing the most frequent mistakes helps you catch them in your own work before a professor or supervising attorney does.

Formatting Mistakes

• Using italics when you should underline (or vice versa) based on whether you're writing an academic paper or a practitioner document
• Incorrect spacing between citation elements (e.g., no space between "F." and "3d" in "F.3d")
• Misplaced or missing periods and commas
• Inconsistent capitalization of party names

Incorrect Abbreviations

• Using non-standard abbreviations instead of the ones listed in the Bluebook tables
• Confusing jurisdiction abbreviations with postal codes ("Cal." not "CA")
• Failing to abbreviate words that the Bluebook requires to be shortened in case names (Rule 10.2.2 lists words that must be abbreviated)
• Getting journal name abbreviations wrong in law review citations

Improper Use of Signals

• Using see when no signal is appropriate (i.e., when the source directly states the proposition)
• Omitting a signal when one is needed
• Failing to provide an explanatory parenthetical when the relevance of the source isn't obvious
• Listing authorities in the wrong order under a signal

Bluebook Updates and Revisions

The Bluebook is periodically revised, and staying current matters. Rules that were correct under one edition may change in the next.

Recent Changes

The 21st edition (released in 2020) is the most current print edition. Notable updates include expanded guidance on citing electronic and online sources, modifications to certain abbreviation conventions, and refinements to formatting rules. The Bluebook also maintains an online edition that can be updated between print releases.

Future Developments

The trend is toward more frequent digital updates rather than waiting for new print editions. There are ongoing discussions in the legal community about simplifying citation rules and better integrating citation-generation tools. As legal research increasingly moves online, expect continued evolution in how electronic sources are cited.

The best habit you can build: always confirm which edition your school or court requires, and check for updates before submitting any document.