Relative Clauses: Restrictive & Nonrestrictive

A clause is a group of related words that contains a subject and a verb. It is distinguished from a phrase, which is simply a group of related words. A clause can be independent, meaning it could be its own sentence. For example, “The statute’s language is vague.” A clause could also be dependent, meaning it depends on an independent clause for its meaning. For example, ”Because the statute’s language is vague, it is unconstitutional.”

Relative clauses are a type of dependant clause and are introduced by a relative pronoun (which, that, who, whichever, whoever, whom, whomever, and of which). The relative pronoun is the subject of the clause’s verb. Relative clauses might be restrictive or nonrestrictive. A nonrestrictive clause is not essential to the sentence’s meaning and can be removed without significantly altering it. Conversely, a restrictive clause restricts or limits the noun it modifies. When the clause should be nonrestrictive, precede it with “which” and set it off with commas. When the clause should be restrictive, precede it with “that.”  For example, the sentence ”Possession of the firearms, which are operable, is illegal” has a different meaning than “Possession of the firearms that are operable is illegal.” In the latter, possession of only the operable firearms is illegal and the existence of other inoperable firearms is contemplated. In the former, the use of a nonrestrictive clause indicates that all of the firearms are operable.

When a relative clause modifies a person, “who” is used. Whether the clause that follows “who” is nonrestrictive or restrictive depends on whether the clause is set off with commas. For example, “Joan’s friend, who was in the car, is liable,” (nonrestrictive) versus “Joan’s friend who was in the car is liable” (restrictive). The nonrestrictive clause indicates that Joan has only one friend;  the restrictive clause signifies that Joan’s other friends were not liable. It would be improper to state, “Joan’s friend, who was in the car, is liable, but the others were not,” because use of the nonrestrictive clause indicates that no other friends exist.

Generally, however, whether a clause should be restrictive or nonrestrictive is up to the writer and based on the meaning that the writer wants to convey. The writer must make sure that the sentence conveys the precise meaning by closely examining whether a clause should be restrictive or nonrestrictive. It is also important to examine whether clauses are restrictive or nonrestrictive when interpreting and applying statutory language and caselaw. The subtle differences in meaning between restrictive and nonrestrictive clauses are opportunities  to make legal arguments that support a position or undermine an opponent’s.