California Style Manual vs. Bluebook Case Citations

Writing a legal document for a federal court instead of a California court (or vice versa)? There are many key case citation distinctions between the California Style Manual and Bluebook that you should be aware of.

This article provides some helpful examples so you can get it right when preparing your next brief, motion, or appendix.

Why compliant brief formatting matters

It may not be easy to remember all the technical differences between the California Style Manual and Bluebook, but it’s important, because if you don’t get it right:

  1. You risk looking unprofessional before the court, as well as your client
  2. You risk having your brief rejected, which can delay and potentially jeopardize your case.

Here are some of the important citation distinctions to keep in mind when preparing briefs for a California court versus a federal court.

Formatting citations to authority

Interestingly enough, in California, citations to authority may be in the style established by either the California Style Manual or the Bluebook.1

Although this rule authorizes parties to choose their preferred citation style, California courts adhere to the California Style Manual and encourage writers to do the same.2 Therefore, it’s best practice to use the California Style Manual in California state courts and the Bluebook in Federal courts.

Formatting citations to the record

When it comes to basic case citations, under the California Style Manual the citation must include the case name, date, and reporter respectively.3 This form contrasts with the Bluebook, which requires the date at the end of the case citation.4

Further, while the Bluebook allows for an option of italicizing or underlining the case name, the California Style Manual only allows for italics.5

The small details: commas, parentheses, spacing

Differences also arise in punctuation and spacing. Unlike the California Style Manual, the Bluebook requires a comma after the case name and spaces in the name of the specific reporter.6

Most notably, the California Style Manual differs by instructing writers to use parentheses around citations and brackets to enclose any unofficial parallel citations.7 It’s also important to note that the period at the end of the citation must be placed inside the parentheses.8

Taking these rules into account, a case citation properly formatted to the California Style Manual appears as:

(Engle v. Vitale (1962) 370 U.S. 421.)

…whereas a case citation properly formatted to the Bluebook appears as:

Engel v. Vitale, 370 U.S. 421 (1962).

In general, when it comes to formatting case citations, consistency is key. Inconsistency can decrease credibility, making it that much more important to adhere to the same formatting style throughout your legal document.

When and when not to use supra

If you regularly prepare briefs for California state courts, then you’re likely familiar with the short citation form “supra”.  Under both the California Style Manual and the Bluebook, once a case is cited in full, later references to that opinion use abbreviated citation forms.9 A big distinction between the two style manuals is when supra may be used to reference these prior citations. 

Pursuant to the California Style Manual, the first reference to a case in any subsequent paragraph must include the case name, supra, the reporter and volume, and page numbers.10 Applying these rules, a short citation of a case properly formatted to the California Style Manual appears as: 

(People v. Barton, supra, 12 Cal.4th at p. 187.)

This, however, differs from the Bluebook form where supra is not used to reference prior case citations.11 A short case citation properly formatted to the Bluebook appears as:

Engel v. Vitale, 370 U.S. at 430.

Additionally, the Bluebook does not allow supra to be used to refer to statutes, constitutions, legislative materials, restatements, model codes, or regulations, except in extraordinary circumstances.12

On the other hand, supra may be used to refer to legislative hearings; court filings; books; pamphlets; reports; unpublished materials; non-print resources; periodicals; services; treaties and international agreements; regulations, directives, and decisions of intergovernmental organizations; and internal cross-references.13

When to use id. versus ibid.

The California Style Manual and the Bluebook also have technical differences around the use of ibid. and id.—two short form citations used when a case has already been cited in full.

Under the California Style Manual, ibid. is used to refer to an identical citation within the same paragraph when no intervening authority has been cited.14 If you are referencing an earlier citation with a different point page, however, the proper form is id. at p. X.15

The Bluebook’s form of ibid. is id., and they function nearly identically. The Bluebook provides that id. is proper when referring to immediately preceding, identical authority.16 Similar to the California Style Manual, when a subsequent citation refers to a different page number, you should use id. at X.17        

4 key rules for getting ibid. / id. right

To avoid misusing ibid. and id. as short forms of cases, remember these four key rules:

  1. ibid. and id. are proper only when referencing an immediately preceding case with no intervening authority
  2. ibid. and id. may not be used to cite to the last case in the previous paragraph even if there is no intervening authority
  3. references within footnotes are styled as references in different paragraphs
  4. ibid. and id. are improper when the previous citation was a string citation with two or more cases.18

Using AI to automate brief formatting

Is your head spinning yet?

Citation formatting is just one of the many small technical details you need to get right when creating a brief for either a California or federal court.

It’s a lot of minute, ticky-tacky details to remember—particularly if you don’t file in that court often—and frankly, it’s tedious. When you’re up against a filing deadline, you probably want to use your limited time and brain power to refine and perfect your argument.

For that reason, many attorneys are turning to AI-assisted automated brief formatting to help transform their drafts into locally-compliant, ready-to-file digital briefs. This video shows how it works.

AI automation can both free up your time and give you the confidence that your brief complies with all the applicable conventions of either the California Style Manual or the Bluebook—so you don’t have to worry about it.

Want to see an example of a compliant brief TypeLaw AI automation helped prepare for 11th Circuit Court of Appeals?

Request a sample brief

1 Cal. Rules of Ct., rule 1.200.
2 Cal. Rules of Ct., rule 8.887(c)(1); Advisory Com. com., Cal. Rules of Ct., rule 8.204.
3 Cal. Style Manual, § 1:1.
4 B2.
5 B2; Cal. Style Manual, § 1:1.
6 B10; Cal. Style Manual, § 1:1.
7 Cal. Style Manual, § 4:57.
8 Cal. Style Manual, § 1:1.
9 Cal. Style Manual, § 1:2; B10.2.
10 Cal. Style Manual, § 1:2.
11 B4.
12 B4.
13 B4.
14 Cal. Style Manual, § 1:2.
15 Cal. Style Manual, § 1:2.
16 B4.
17 B4.
18 Cal. Style Manual § 1:2; B4.