Ban and/or.
And/or dates from the mid-19th century. Although lawyers and courts have vilified and/or for most of its life, this bit of legalese continues to infest legal writing and create ambiguity.
The literal sense of and/or is “both or either,” so that A and/or B means (1) “A,” (2) “B,” or (3) “both A and B.” Since and/or has a literal sense, what’s the problem? “Both or either” suggests a choice, but and/or is often used in contexts where logically there is no real choice. This makes the drafter’s intent hard to discern.
Courts are often asked to decide the intended effect of and/or. For example, if a provision states “Robert and/or Jane must sign to make this agreement valid,” will the agreement be valid if only Robert or only Jane signs—can they really bind each other without the other’s consent? Or is it valid only if both Robert and Jane sign?
About half the time, and/or means or:
Ex.: A sign: “No food and/or drink allowed.” [It says that each is disallowed. Read: “No food or drink allowed.”]
Ex.: Language in a rental agreement: “Williams must give the owner prompt notice of noise, traffic, and/or pet violations observed on the property.” [What is Williams required to give notice of: all three violations occurring at once, or in some combination, or individually? Read: “Williams must give the owner prompt notice of all noise, traffic, or pet violations observed on the property.” (If Williams must give notice of each type individually, it follows that he must also give notice of any combination of them.)]
And about half the time, and/or means and:
Ex.: A provision in a statute: “All applicable state and/or federal regulations apply to the transfer of goods.” [Or falsely suggests a choice between regulations. Read: “All applicable state and federal regulations apply to the transfer of goods.”]
Ex.: A statement in a report: “The team of lawyers, paralegals, and/or mediators resolved the case quickly for their client.” [Who was on the team? Did they all contribute to the resolution or not? Read: “The team of lawyers, paralegals, and mediators resolved the case quickly for their clients.”]
In most legal drafting—when linguistic precision is essential—it’s best to add the words or both or either:
Ex.: A provision in a statute: “Violation of this provision is punishable by imprisonment of up to 5 years and/or a $10,000 fine.” [If the violator can be both imprisoned and fined, read: “Violation of this provision is punishable by imprisonment of up to 5 years, a $10,000 fine, or both.” If only one punishment can be levied, read: “Violation of this provision is punishable by either imprisonment of up to 5 years or a $10,000 fine.”]
If the document lists several items, and not all are required, introduce the list with any of the following:
Ex.: A provision in a regulation: “To prove residency, please provide (1) a valid, unexpired driver’s license; (2) a valid, unexpired voter-registration card; and/or (3) a W-2 or 1099 from the current tax year.” [Does the applicant need to provide just one or all of the documents? Read: “Any of the following documents will be accepted to verify a person’s residency: (1) a valid, unexpired driver’s license; (2) a valid, unexpired voter-registration card; or (3) a W-2 or 1099 from the current tax year.”]
Small wonder that and/or has been held to invalidate provisions in affidavits, wills, indictments, judgments, contracts, statutes, and findings of fact.
Although using and/or seems like a quick and easy drafting tool, it’s more of a quick and dirty one: it too often reflects a failure to think something through or to understand what the parties intend. It creates room for disagreement and litigation. After some practice, you’ll find it surprisingly easy and workable to avoid the phrase. In the long run, the extra effort you make to choose between and and or will save you much effort, money, or both.
Further reading:
Garner’s Dictionary of Legal Usage 57–58 (3d ed. 2011).
Garner’s Modern American Usage 45–46 (3d ed. 2009).
Garner, Legal Writing in Plain English 133–34 (2d ed. 2013).
R.W. Burchfield, The New Fowler’s Modern English Usage 53 (3d ed. 1996).
Antonin Scalia & Bryan A. Garner, Reading Law: The Interpretation of Legal Texts 116–25 (2012).
David Mellinkoff, The Language of the Law 147–52, 306–10 (1963).