6.5.6 Cases That Cite Other Cases
A citation dilemma for many legal writers is what to do when citing an excerpt of a case that has quoted another case. Traditionally, writers have been encouraged to cite the original source, as the writer does in the following example:

BAD EXAMPLE
A person possesses a reasonable expectation of privacy, and thus a search occurs when an officer makes an observation from a location within the curtilage of a private home.
See Oliver v. United States, 466 U.S. 170, 180 (1984). Curtilage, “the land immediately surrounding and associated with the home,” is “the area to which extends the intimate activity associated with the ‘sanctity of a man’s home and the privacies of life.’” Id. (quoting Boyd v. United States, 116 U.S. 616, 630 (1886)).Although this guideline may be appropriate for law review articles and other publications, it is not always the best rule for brief writing. In this situation, it is doubtful that the court needs to know about an 1886 case that is the origin of the “sanctity” language.
Of course, a legal writer may need or want to cite the original source to give added credence to a discussion of a case decided by a nonmandatory court. In the example below, from a petitioner’s brief in Minnesota v. Carter, the writer is discussing a California case that applied Minnesota v. Olson, a significant United States Supreme Court case that had been previously cited in that same section of the brief:

GOOD EXAMPLE
In 1992, a California court found that a defendant who moved to suppress items seized at his brother’s apartment while the defendant was babysitting there had a legitimate expectation of privacy. People v. Moreno, 3 Cal.
Rptr. 2d 66, 70 (Cal. Ct. App. 1992). The court cited Olson and indicated that, “[l]ike ‘staying overnight in another’s home,’ babysitting ‘is a longstanding social custom that serves functions recognized as valuable by society.’” Id. at 70 (quoting Olson, 495 U.S. at 98).If the reviewing court knows that the California court was basing its decision on United States Supreme Court authority, the court may give that California decision more weight in a brief, especially if the reviewing court is the United States Supreme Court. Thus, if knowing the origin of the cited language could affect the Court’s understanding or acceptance of your argument, identify that source. This situation does not occur regularly in legal writing; generally, if the origin of the language is significant, the writer should go to the original source and cite that authority in addition or instead. It is only when the relationship between the two sources is significant — as it is when an on-point nonmandatory court applies a rule from a mandatory court — that the reader is likely to be interested in the origin of the quoted language.
In most other situations, however, judges looking at the citations supporting an argument want to know only that a valid court made that statement in an analogous case. They usually have little or no interest in the original source of particular words or phrases. If the cited opinion is a valid authority for that quote, it matters only that an authoritative court made the statement in its majority opinion and that the statement is not dicta. Even if that court misinterpreted the original language, what usually matters is the court’s belief that the language was appropriate to apply to the particular set of facts that was before it. Thus, determine whether your argument would be more effective if the court you are writing to knew the original source of the quoted language. If knowing the source would not improve your argument’s effectiveness, you can omit the citation, as long as you inform the court that you are doing so:
GOOD EXAMPLE Curtilage, “the land immediately surrounding and associated with the home,” is “the area to which extends the intimate activity associated with the ‘sanctity of a man’s home and the privacies of life.’” Id. (citation omitted).
Substituting the “citation omitted” parenthetical phrase for the full citation will allow those who wish to track the original language the opportunity to do so. Most judges and clerks, however, will be grateful that you have not cluttered the brief with irrelevant citations.