What is a signal actually doing?
A signal is a one- or two-word instruction about the relationship between your sentence and the authority you cite. It answers a question the reader would otherwise have to answer by pulling the case: does this source say what you just said, or does it merely point in that direction? Rule 1.2 lists the signals and defines each one; the definitions are short, and you should read them once carefully rather than absorbing them by osmosis from briefs you have seen.
Signals divide into four functional families: supportive (no signal, e.g., accord, see, see also, cf.), comparative (compare ... with ...), contradictory (contra, but see, but cf.), and background (see generally). Everything else about signals — ordering, punctuation, whether you need a parenthetical — follows from which family a signal belongs to.
One structural point students miss: the absence of a signal is itself a signal. Leaving the space blank is an affirmative representation that the cited source directly states your proposition, identifies the source of a quotation, or identifies an authority you referred to in the text. If that is not true, you have miscited.
Which supportive signal do you use?
Work down the list in order of decreasing directness. If the source says it, use no signal. If you had to reason from the source to your sentence — even one small step — use "see." If the source is extra support that is less direct than what you already cited, use "see also." If the source supports a different but sufficiently analogous proposition, use "cf."
"E.g." means the cited authority is one of several that state the proposition, and citing the rest would not be helpful. It is the honest way to avoid a twelve-case string cite. It also combines with other signals: "See, e.g.," and "But see, e.g.," are both correct and common.
"Accord" is narrower than students think. Use it when your text quotes or discusses one authority and other authorities state the same thing, so you cite the discussed source first and the others after "accord." It is also the conventional signal for showing that the law of one jurisdiction agrees with the law of another.
- [no signal] — the source directly states the proposition, is the source of a quotation, or is identified in your text.
- e.g. — the cited source is one example among many that state the proposition.
- accord — additional sources that agree with the one you just quoted or discussed.
- see — the source supports the proposition by obvious inference; it does not say it outright.
- see also — additional, less direct support; a parenthetical is encouraged.
- cf. — the source supports an analogous proposition; explain the analogy in a parenthetical.
How do the contradictory and background signals work?
The negative signals mirror the positive ones. "Contra" is the opposite of no signal: the source directly states the contrary of your proposition. "But see" is the opposite of "see": the source clearly supports a contrary proposition without stating it flatly. "But cf." is the opposite of "cf.": the source supports a proposition analogous to the contrary of yours, and it needs a parenthetical to make the analogy visible.
There is a small punctuation rule worth knowing because journal editors check it: when a negative signal directly follows another negative signal in the same citation sentence, drop the "but." So you get "Contra Smith ...; see Jones ..." — the second negative signal appears as "see," not "but see," because the reader already knows you are in contrary territory.
"See generally" is the background signal. It means the source provides useful background on the general subject, not support for the specific sentence. Treatises, law review articles surveying an area, and Restatement commentary often belong here. A parenthetical explaining the relevance is encouraged, because otherwise the reader has no idea why you sent them there.
How do you order signals and authorities?
Rule 1.3 sets the order: [no signal], e.g., accord, see, see also, cf., compare ... with ..., contra, but see, but cf., see generally. Signals of the same basic type (all supportive, all contradictory) go in one citation sentence separated by semicolons. Signals of different types go in separate citation sentences. So supportive authorities get their own sentence, then a new sentence beginning with "But see" or "Contra," then a final sentence beginning with "See generally."
Within a single signal, Rule 1.4 controls. The general hierarchy is constitutions, statutes, treaties, cases, legislative materials, administrative materials, then secondary sources. Within cases, federal comes before state; within federal, Supreme Court, then courts of appeals, then district courts; within each rank, reverse chronological order (newest first). The one override: if a single authority is considerably more helpful than the others, you may put it first regardless of rank.
"Compare ... with ..." is a signal, not a sentence, and both words are italicized. The form is: Compare [cite], with [cite]. If you have more than one authority on a side, use "and": Compare [cite], and [cite], with [cite], and [cite]. Note the commas before "with" and before each "and." A comparison that the reader cannot decode is worse than no citation, so include a parenthetical explaining what the contrast shows.
Which signals require an explanatory parenthetical?
Rule 1.5 governs explanatory parentheticals, and the strength of the requirement tracks the signal. For "cf." and "but cf.," a parenthetical is strongly recommended — treat it as mandatory in journal work, because the entire point of the signal is that the connection is analogical and therefore not obvious. For "see also" and "see generally," a parenthetical is encouraged. For "compare ... with ...," you need one unless the comparison is self-evident, which it rarely is.
Parentheticals ordinarily begin with a present participle and no capital letter: (holding that ...), (noting that ...), (rejecting the argument that ...). A quoted phrase or a short statement that is not a full sentence can also stand alone in the parentheses. Parentheticals come after the date parenthetical and before any subsequent-history citation.
Use the parenthetical to do the work your sentence cannot. "Cf. Jones v. State, ..." tells the reader nothing. "Cf. Jones v. State, ... (applying the same waiver analysis to a Miranda warning delivered in Spanish)" tells the reader why you bothered.
How do you format signals typographically?
In law review footnotes and in court documents alike, signals are italicized. The Bluepages typeface rules for court documents (B2) and Rule 2 for law review pieces both put signals in the italicized category, along with case names, introductory words like "quoting" and "citing," and cross-reference words like "id." and "supra." Older practice of underlining rather than italicizing is still accepted in many courts; check local rules and your professor's preference.
Note the periods and commas. "E.g." and "cf." carry periods because they are abbreviations; "see," "accord," "contra," and "compare" do not. "E.g." is always followed by a comma: "See, e.g., Brown v. Board of Education, ...." The other signals are followed directly by the citation with no comma.
When a signal functions as a verb in a textual sentence — "See Rule 1.2 for the full list" — it is not italicized, and you do not abbreviate it. Do not write "Cf. the Restatement" in running text; write "Compare the Restatement."
Where do people lose points?
The dominant error is signal inflation: using "see" for everything because it looks scholarly. If your sentence is "A federal court must have subject matter jurisdiction" and you cite a case that says exactly that, no signal is correct, and "see" is wrong. The reverse error — no signal in front of a case that requires two inferential steps to reach your point — is more serious, because it is closer to a misrepresentation than a formatting slip.
The second common error is a bare "cf." or "compare" with no parenthetical. The third is mixing signal families in one citation sentence, usually "see X; but see Y" run together with semicolons. Split them: one sentence ending in a period, then "But see Y."
Practices vary. Most federal judges and most practitioners use signals loosely and will not notice a debatable "see." Law journals, moot court competitions, and 1L legal writing graders will. The ALWD Guide to Legal Citation uses essentially the same signal set with the same meanings, so switching systems does not change the analysis. Confirm which Bluebook edition your journal or course requires — the signal rules have been stable across recent editions, but rule numbering and peripheral formatting rules do move.