If you ever write a brief for the U.S. Fourth Circuit, you'd better know the difference between restrictive and nonrestrictive adjective clauses, i.e., a clause modifying a noun and starting with that or which. And you'd better punctuate correctly. Your brief might be read by Judge William B. Traxler, Jr., who, as a district judge, wrote the following criticism of Congress's usage and punctuation in a provision of CERCLA (Coomprehensive Environmental Response, Compensation, and Liability Act):
Section 9607(a)(4) provides: "from which there is a release, or a threatened release which causes the incurrence of response costs, of a hazardous substance, shall be liable ..." The punctuation and grammar of this section affect the issue of causation. The perennial distinction between "that" and "which," along with the concomitant punctuation of the type of clauses these words introduce, presents more than idle speculation. A restrictive clause modifies a sentence differently from an identically-phrased nonrestrictive clause. A restrictive clause identifies a subset of the object described and directs the meaning of the sentence to that subset. A nonrestrictive clause, however, modifies the entire set as already described. Nonrestrictive clauses must be set off by commas, while restrictive clauses must not be set off by commas. "That" cannot be used to introduce a nonrestrictive clause; conversely, "which" should not be used to introduce a restrictive clause. Since "which" and not "that" is used in § 9607(a)(4), the implication is that the clause is nonrestrictive. This, of course, means that a "threatened release" is subject to the causation requirement because the causation clause of the statute is introduced by "which." Although seemingly academic, the distinction is genuine. The problem with § 9607(a)(4), however, is complicated by the fact that the causation clause does not follow a comma: the lack of a comma suggests that the modifying clause is restrictive; the word "which" suggests that the clause is nonrestrictive. This distinction reflects CERCLA's inherent ambiguity. "Which causes" as opposed to "that causes," particularly when coupled with punctuation errors, results in uncertainty as to whether liability exists from a release without the incurrence of response costs. See generally H. Ramsey Fowler, The Little, Brown Handbook 601 (3d ed. 1986). The court, however, need not attempt to reconcile this legislative nightmare because the Plaintiffs in the present action have not demonstrated consistency with the NCP, which proves fatal to their action.
Rhodes v. County of Darlington, South Carolina, 833 F. Supp. 1163, 1191 n.18 (D.S.C. 1992).