This is a guide to the Bluebook system of American legal citation. The information here can help anyone who is writing a scholarly legal paper in the United States, including JD students, LLM students, and SJD students.
The Bluebook is currently in its 21st edition, released in June 2020. It is available in two formats: as a print book, and as an electronic publication. To buy a print copy or a subscription to the electronic version, visit https://www.legalbluebook.com/.
All references to print book page number in this guide are from the 21st edition.
The Bluebook has two sections:
Since law school work focuses on academic writing, this guide describes and explains the rules in the Whitepages section.
Table 1 (p. 227) has jurisdiction-specific rules for citing U.S. federal and state cases, statutes, and other primary legal materials.
Table 2 has rules for citing sources from selected foreign jurisdictions. It is no longer in the print version of the Bluebook, but it is freely available online.
Tables 3 (international organizations, p. 299) and 4 (treaties, p. 302) have rules for citing international sources.
Finally, many Bluebook rules require certain names, words, and phrases to be shortened. Tables 6-16 (starting on p. 304) list these abbreviations.
To create a correct Bluebook citation, follow this quick six-step process:
To see an example of how this process works with an article from the NY Times website, check out the short video below.
To download the PowerPoint slide deck shown in this video, click the icon below.
If you want them to be 100% correct, then no.
The Zotero Citation Management System has an option for generating Bluebook-style citations. However, Zotero's citations are frequently not Bluebook-perfect (especially for primary sources like cases and statutes), so you will have to fix them if you want them to be right.
The PowerNotes Content Management System also has an option for generating Bluebook-style citations. It does Bluebook a bit better than Zotero, but its citations are not perfect either. If you want them to be correct, you have to fix them.
Anything you download from HeinOnline as a PDF will include a Bluebook citation on the first page of the PDF. Those citations are often close but not entirely right. For example, Hein-generated citations do not use small caps for book and journal titles. So, again, you can use them but you will have to fix them.
Lexis and Westlaw show citations for every case. These are generally correct in that the letters and numbers are right. But many cases are reported in multiple reporters, and the Bluebook has requirements regarding which citation version you use depending on the court. So you can and should use them, but you still have to use Rule 10 and Table T1 to make them perfectly compliant with the Bluebook rules.
In other words, there is no getting around learning the Bluebook if you are writing an American legal academic paper that requires citations to be in Bluebook format. No automated process will do a better Bluebook citation than a human being reading and applying the rules.
Yes! Right inside the front cover there is a quick guide to the major rules, with citation examples. Use this as a quick reference if you can't remember which rule covers which type of source.
Rule 18 has rules for citing internet sources, websites, documents found online, blogs, social media posts, etc. This guide has a short video that demonstrates how this works for a website (click Bluebook Training Videos in the table of contents to the left of this text to navigate to it).
Remember, the Bluebook really prefers that you cite to a print source. It has gotten more flexible over the years. However, for something like a law review article, even if you found it online, you still need to follow the instructions in Rule 16 to cite it.
Instructions for doing this are in Rule 3.5: Internal Cross-References.
If you cited only one source in footnote #1, and you want to cite the exact same source in footnote #2, that is when you use id. Only the source has to be the same, not the page or section.
In the below example, footnote #2 is citing page 200 of the Messi case.
For secondary sources like law review articles and books, if you want to cite a source that you cited longer ago in your paper than the previous footnote, you can use supra.
When you do a supra citation, you have to use the same font specifications as you did in the original citation. What does that mean? Check out footnote #3 below, which cites a book. According to rule 15, both the author and the title of the book must be in small caps. This same book is also cited in footnotes #5, #7, and #11. In each of those, the author's name is in small caps.
This rule is slightly different for cases, however.
Footnote #1: Messi v. Haaland, 100 F.4th 197 (9th Cir. 2021).
Footnote #2: Id. at 200.
Footnote #3: Kylian Mbappé, Comparative Constitutional Jurisprudence in the Twenty-First Century 15 (2022).
Footnote #4: Messi, 100 F.4th, at 201.
Footnote #5: Mbappé, supra note 3, at 58-59.
Footnote #6: Manuel Neuer, Why the Judiciary Needs Term Limits, 200 Harv. L. Rev. 1, 7 (2022).
Footnote #7: Mbappé, supra note 3, at 88.
Footnote #8: See Neuer, supra note 6, at 9-11 (describing how establishing term limits for judges in Germany has instilled more confidence in that country's judiciary).
Footnote #9: Zinchenko v. Davies, 101 F.4th 408, 409 (2nd Cir. 2022).
Footnote #10: Id. at 415.
Footnote #11: See generally Mbappé, supra note 3.
Footnote #12: But see id. at 227-30 (outlining Mbappé's argument that constitutional court judges should also be trained in areas other than law).
Footnote #13: Zinchenko, 101 F.4th at 410; see also Neuer, supra note 6, at 15-16.
Footnote #14: Messi v. Haaland, 100 F.4th 197, 202 (9th Cir. 2021).
It's a fact of life that footnote numbers change as we add and remove footnotes from our paper during the editing process.
Fortunately, Microsoft Word has a feature that can help. There is a video further down in this guide that explains how to use Word's Internal Cross-Reference feature to add footnote reference numbers to supra citations (click Bluebook Training Videos in the table of contents to the left of this text to navigate to it).
If you use this feature, these numbers will be connected to the source that you're citing. What does that mean? Suppose you first cite a book by Sandra Jones in footnote #28 in your paper, like this:
Then, you cite that same book in footnote #34, like this:
What happens if, later on, you add another footnote to your paper BEFORE the Jones book citation that has been in footnote #28? That's right: that Jones book citation is pushed back to footnote #29. That also means that the supra note number in footnote #34 (which is now footnote #35) needs to change, from 28 to 29.
When you first create footnote #34, don't manually type "28" after "supra note." Instead, insert it as a cross-reference, following the instructions in the video below. That way, when it needs to be updated when the footnote numbers change, you can tell Word to do that automatically. That procedure is also explained in the video.
If you do this every time you add a supra citation, you will be able to update all of the numbers in all of the supra citations in your paper in a few keystrokes, regardless of how many footnotes you have. Please consider using this headache-preventing device.
Introductory signals explain why and how you are citing and using a source.They are listed below, and rule 1.2 explains their use.
In the example below, signals are used in footnotes #8, #11, and #12.
When using a signal like "See" or "But see," you may want to use a parenthetical to explain why you are citing a particular source. This is shown in footnotes #8 and #12 in the example below. For more information about how this works, see rule 1.5: Parenthetical Information.
Instructions for citing foreign (non-English) materials are provided in detail in Rule 20.2 and in the individual country sections in Table T2 (which is freely available online; note not every jurisdiction is covered).
Generally, when it comes to language version, you need to cite the source you are referring to, as detailed in rules 20.2.2 and 20.2.5.
If you are referring to a non-English primary source in its original language, you should cite the original-language version. Here's an example of this from the German version of the Political Parties Act:
If you are referring to a primary source that was translated into English, you should cite the translated version. Here's an example of this from an English-language translation of the Swiss Civil Procedure Code that is available on the Swiss government's website:
Cite foreign books just like U.S. books according to rule 15. For articles from foreign periodicals and newspapers, see rule 20.6.
Providing an English-language translation of foreign-language article titles is permitted, but not necessary. There is no stated rule for providing translations of book titles. Remember, however, if your paper is targeting a U.S. audience, many readers will find those kinds of translations helpful.
Americans capitalize most words in titles, and the Bluebook's capitalization rule, Rule 8, reflects this preference:
Incorrect article title capitalization:
Hearing the voiceless: a respected judge on putting the rights of crime victims above those of defendants
Correct article title capitalization:
Hearing the Voiceless: A Respected Judge on Putting the Rights of Crime Victims Above Those of Defendants
In American legal writing, as opposed to that in many other countries, place the footnote number AFTER punctuation marks, including periods, commas, quotations marks, etc. Note, however, that there are two types of punctuation marks that should have the footnote number placed before them: colons, and dashes. This is shown in the example accompanying rule 1.1.
We have some short videos of Bluebook tips that are based on the FAQ in this guide.
The first tip video explains the answers to both FAQ #3 (using id and supra) and FAQ #4 (using Word's internal cross reference feature), all in one 3:30 video!
The next tip video discusses FAQ #2 - using rule 18 to cite online sources. It also talks about perma.cc, the Harvard Law School Library Innovation Lab's website archival tool.
Here's another video that was made based on a recent question we received in the research service department. It describes how to cite a federal statute as a session law (using rule 12.4) and not how it was codified in the U.S. Code. Examples are given for two types of citations: to a chapter number (for very old statutes), or to a public law number (for newer statutes).
Below is a two-part recording of a Bluebook training class offered by Jennifer in March 2020. Although it references the 20th edition of the Bluebook, the class is still relevant and provides a good basic introduction to general Bluebook style and citation rules for US and foreign sources.
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