California Legal Citations: CSM vs. Bluebook Rules

In a California state court filing, every citation must follow either the California Style Manual (CSM) or The Bluebook, and whichever you pick has to be used consistently across the entire document under California Rule of Court 1.200.¹ Most California state court practitioners use the CSM because it was built around California’s official reporters, codes, and regulations. The California legal citation format that follows walks through how the CSM handles the sources you will actually cite, and where it diverges from the Bluebook habits you may have picked up in law school.

Choosing Between the CSM and the Bluebook

Rule 1.200 does not prefer one manual over the other. The choice belongs to the filing party, and both are equally acceptable in state court.¹ If you are filing in federal court in California, the Bluebook is the standard expectation.

The consistency requirement is strict. You cannot use CSM formatting in one section and Bluebook formatting in another. Pick one before drafting begins, and if you are working with co-counsel who trained on a different manual, resolve that at the outset.

How a California Case Citation Looks Under the CSM

California Supreme Court opinions appear in the California Reports (Cal., Cal.2d, Cal.3d, Cal.4th, or Cal.5th, depending on the series). Court of Appeal opinions appear in the California Appellate Reports (Cal.App. through Cal.App.5th). Under the CSM, the official reporter citation always comes first. The unofficial California Reporter citation (Cal.Rptr., Cal.Rptr.2d, or Cal.Rptr.3d) follows in square brackets as a parallel citation.

A complete CSM citation looks like this:

People v. Smith (2020) 10 Cal.5th 100 [270 Cal.Rptr.3d 10]

Several things are happening in that one line. The case name is fully italicized, including the “v.” The year sits right after the case name, not at the end. The parallel citation is in square brackets rather than parentheses.² If you generate citations from Westlaw or Lexis, check the output before pasting it in. Those services often add extra information and misplace spacing for CSM format.

Pinpoint Citations

When you point to a specific passage rather than the case as a whole, include both the first page of the opinion and the page where the material actually appears:²

People v. Smith (2020) 10 Cal.5th 100, 115 [270 Cal.Rptr.3d 10]

The “100” is the inception page; the “115” is what you are directing the reader to. Dropping the inception page in a full citation makes the case harder to find. If you give a pinpoint for the official reporter, give one for the parallel citation too when possible.

Where the CSM Diverges From the Bluebook

Four differences cause most of the errors in documents that try to follow CSM style.

Date placement. The Bluebook puts the year at the end of a case citation in parentheses. The CSM puts it right after the case name.

Bluebook: Bush v. Gore, 531 U.S. 98 (2000)
CSM: Bush v. Gore (2000) 531 U.S. 98

Official reporters. The CSM leads with the official California Reports or California Appellate Reports citation, then adds the California Reporter in brackets. The Bluebook typically cites only the West regional reporter for state cases.

Statute punctuation. The CSM uses a comma between the code abbreviation and the section symbol, as in (Bus. & Prof. Code, § 16700). The Bluebook omits that comma: Cal. Bus. & Prof. Code §§ 16700–16703.²

Rules of Court. The CSM writes (Cal. Rules of Court, rule 8.200(a)(5)). The Bluebook shortens it to Cal. R. 8.200(a)(5).

Introductory signals are also formatted differently, which comes up below.

Citing California Statutes

California law is organized into subject-matter codes: the Civil Code, Penal Code, Family Code, Evidence Code, Business and Professions Code, and many others. The format depends on whether the citation sits inside parentheses or runs in the text of a sentence.

Inside parentheses, abbreviate the code name, add the comma, then the section symbol and number:

(Civ. Code, § 1717.)
(Pen. Code, § 459.)
(Bus. & Prof. Code, § 16700.)
(Fam. Code, § 2610.)

In running text, spell the code name out in full: “Penal Code section 459 defines burglary as entering a structure with the intent to commit theft or any felony.”²

For subdivisions, the CSM uses “subd.” in parentheses: (Civ. Code, § 1717, subd. (a).) Missing the comma between the code abbreviation and the section symbol is one of the most common formatting errors in filings that claim to follow the CSM.

Citing the California Constitution

Constitutional provisions use a compact format with abbreviated article and section references:²

(Cal. Const., art. VI, § 10.)

For multiple articles, use the plural: (Cal. Const., arts. IV, V & VI.) For subdivisions and paragraphs within a section, stack the designations: (Cal. Const., art. XIII, § 28, subd. (f), par. (3).) In running text, spell it out: “Article VI, section 10 of the California Constitution.”

Citing Federal Authorities in California State Court

Filing in state court does not limit you to California sources. Federal cases, statutes, and regulations come up constantly, and the CSM has specific formats for each.

Federal Cases

Federal case citations follow the same date-after-case-name structure. The court identifier goes inside the date parenthetical:

U.S. Supreme Court: Bush v. Gore (2000) 531 U.S. 98
Ninth Circuit: Craig v. United States (9th Cir. 1936) 81 F.2d 816
District Court: Mattel, Inc. v. MCA Records, Inc. (C.D.Cal. 1998) 28 F.Supp.2d 1120, 1126

Supreme Court cases do not need a court identifier because the U.S. Reports citation makes the court obvious. For every other federal court, include the circuit or district abbreviation inside the date parenthetical.²

Federal Statutes

Cite the title number, the code abbreviation, and the section number. Federal statute citations do not use “subd.” for internal divisions. The CSM accepts citations to the United States Code (U.S.C.), United States Code Annotated (U.S.C.A.), or United States Code Service (U.S.C.S.):²

(42 U.S.C. § 1983.)
(26 U.S.C. § 2056(b)(7)(B)(v).)

Federal Regulations

Regulations are cited to the Code of Federal Regulations by title and section, with the C.F.R. edition year in parentheses at the end:²

(32 C.F.R. § 581.3(c)(5) (1997).)

If a regulation has not yet been codified in the C.F.R., cite the Federal Register (Fed.Reg.) by volume and page number, with the specific date of the edition.

Citing California Administrative Regulations

State administrative regulations live in the California Code of Regulations. Cite by title number, the CCR abbreviation, and the section number:

(Cal. Code Regs., tit. 15, § 3084.1.)

Each CCR title covers a broad subject area (title 15, for example, covers Crime Prevention and Corrections). In running text: “California Code of Regulations, title 15, section 3084.1.”

Short-Form Citations for Repeat References

Full citations only appear once. After that, the CSM gives you three tools, and picking the right one depends on where you are in the document relative to the first citation.

Ibid. Use this when citing the exact same authority and exact same page as the immediately preceding citation, with no other authority in between.
Id. at p. [page]. Use this when citing the same authority as the immediately preceding citation but at a different page.
Supra. Use this to refer back to an authority cited in full earlier, after other authorities have intervened. The short form includes a shortened case name, the word supra, the volume and reporter, and the pinpoint page: (Smith, supra, 10 Cal.5th at p. 115.)

The CSM draws a distinction the Bluebook does not: ante and post refer to earlier or later parts of the same opinion, while supra refers to an external authority previously cited. Do not use supra for internal cross-references within an opinion, and do not use ante or post for external citations.²

One more limit: neither ibid. nor id. works when the first citation appeared inside a string of multiple authorities. In that situation, use supra with the case name.

Introductory Signals

When an authority only indirectly supports what you just wrote, the CSM requires a signal to flag that. The common ones, in rough order of support strength:

[No signal]: the authority directly supports the proposition or is the source of a quotation.
See: the authority indirectly supports the text, or you are citing supporting dicta rather than a holding.
See also: additional authority that indirectly supports the proposition.
See generally: helpful background material.
See, e.g.,: the cited case is one example among several that could have been cited.
Cf.: the authority is sufficiently analogous to lend support.
Accord: after a primary authority, introduces other decisions holding the same way, including from other jurisdictions.
Contra: the authority is directly contrary to the stated proposition.
But see: the authority is somewhat inconsistent with the main authority.

Formatting note that catches Bluebook-trained writers: the CSM does not italicize introductory signals.² A parenthetical citation with a signal looks like: (See Bennett v. Spear (1997) 520 U.S. 154, 162.)

Unpublished Opinions

An unpublished opinion from a California Court of Appeal or superior court appellate division generally cannot be cited or relied on in any other case.³ Unpublished opinions are not precedential authority in California.

Two narrow exceptions exist. You may cite an unpublished opinion when it is relevant under the doctrines of law of the case, res judicata, or collateral estoppel, or when the opinion is relevant to a criminal or disciplinary proceeding because it states reasons for a decision affecting the same defendant or respondent.³ If you cite one under either exception, be ready to provide a copy to the court or opposing party on request.

Quoting and Modifying Source Text

When you quote directly and need to omit words, use an ellipsis (three spaced periods) inside a sentence. If the omission spans the end of one sentence and the start of another, use four periods. Spacing matters: no space between a sentence-ending period and the following ellipsis, but a space before the ellipsis for a mid-sentence omission.

Use square brackets for any change you make to the original: altering a capital letter to lowercase, changing a verb tense to fit your sentence, or inserting a clarifying word. If a statute reads “The defendant shall comply,” you might write “[The] defendant shall comply” or “the defendant [must] comply.” Never alter a quotation without brackets, and never use an ellipsis to change the meaning of the quoted passage. Courts notice both.

1
Judicial Branch of California. California Rules of Court – Rule 1.200
2
Sixth District Appellate Program. California Style Manual
3
Judicial Branch of California. California Rules of Court – Rule 8.1115