Legal citation signals are a set of brief abbreviated phrases or words used to clarify the authority or significance of a legal citation as it relates to a proposition. Signals help a reader quickly discern meaning or usefulness of a particular reference when the reference itself does not provide adequate information. Legal citation is the style of crediting and referencing other documents or sources of authority in legal writing. ...

Most citation signals are placed in front of the citation to which they apply. For example, in the paragraph

When writing a legal argument, it is important to refer to primary sources. To assist readers in locating these sources, it is desirable to use a standardized citation format. See generally Harvard Law Review Association, The Bluebook: A Uniform System of Citation (18th ed. 2005). Note, however, that some courts may require any legal papers that are submitted to them to conform to a different citation format.

the signal is the phrase "see generally," which indicates that the citation "The Bluebook: A Uniform System of Citation (18th ed. 2005)" provides general background information on the topic.

Parenthetical signal

The parenthetical signal provides additional information about the citation. Unlike the other signals, it follows immediately after the full citation. It usually is brief, about one sentence, and provides a quick explanation of how the citation either supports or is in disagreement with the proposition. For example: Brown v. Board of Education, 347 U.S. 483 (1954) (overruling Plessy v. Ferguson.)

List of common citation signals

Indicating support:

• [no signal] is appropriate where the cited authority (i) directly states the proposition, (ii) identifies the source of a quotation, or (iii) identifies an authority referred to in the text.
• E.g., means there is more legal authority supporting the same proposition as the original cited authority, but whose inclusion is not helpful, repetitive, or unnecessary.
• Accord usually is used to signify that some persuasive authority also supports the proposition of the quoted authority.
• See signifies that a particular source clearly supports the proposition, but usually not a concise quotation. See is generally the most common signal used in journal articles.^{[citation needed]}
• See also signals support for a given proposition, but not as clearly as see.
• Cf. literally means "compare" and is used to signify significance by analogy. Frequently, Cf. requires parenthetical signals to clarify the importance.
• See generally means that a source provides useful background information. Usually used in the citation of secondary sources.

Indicating contradiction: Precedent is the principle in law of using the past in order to assist in current interpretation and decision-making. ... Analogy is both the cognitive process of transferring information from a particular subject (the analogue or source) to another particular subject (the target), and a linguistic expression corresponding to such a process. ... In historical scholarship, a Secondary source is a work of history written as a synthetic account, usually based on primary sources and other secondary sources. ...

• But see means that the original citation supports the proposition and that the following citation supports something else. There does not need to be a direct contradiction.
• But cf. the following citation supports a contrary position by way of analogy.
• Contra means that the following citation is in direct contradiction with the original source.

Suggesting a useful comparison:

• Compare… with is a literal comparison between two or more sources. Like Cf., this signal is usually accompanied by parenthetical signals to clarify any contradiction.

See also

• Legal citation
• The Bluebook: A Uniform System of Citation. Harvard Law Review Association.