Oregon State Bar Bulletin — APRIL 2016

The Legal Writer

Latin in Legal Writing:
When to Use It, How, and What It Means
By Elizabeth Ruiz Frost

Latin pops up so much in legal writing that it could be tested on the bar exam. Some wise readers may know when to use it and what it all means. To those readers, gratulatione, placere frui postero articulus.1 For the rest of us, here’s a little Latin lesson.

When to Use Latin

Here is the short answer for when to use a Latin word or phrase: rarely. Some Latin words and phrases are unavoidable in legal writing. But like drug store aftershave, a little goes a long way. Writing in plain English requires writers to strip out the 50-cent words and legalese, including Latin phrases. Only use a Latin phrase when no English equivalent exists.

How to Use Latin

Sometimes Latin words and phrases get italicized, and sometimes they don’t. According to Bluebook and the ALWD Guide to Legal Citation, do not italicize a foreign word or phrase if it is so frequently used that it has become a part of the English lexicon. I guess I should stop italicizing taco. Do italicize very long Latin phrases and those that are obsolete or uncommon. (But if it’s obsolete, one might ask why it’s turning up in your writing.) So when is a Latin word no longer foreign? Bluebook and the ALWD Guide provide nonexhaustive lists containing examples. Here are a few:

Still foreign (italicize): vin de table, ignorantia legis neminem excusat, ex dolo malo non oritur action.2

No longer foreign (don’t italicize): ad hoc, res judicata, corpus juris, modus operandi, quid pro quo, de jure, prima facie, en banc, mens rea, res ipsa loquitur.

After checking the nonexhaustive lists in the Bluebook and ALWD Guide, check Black’s Law Dictionary to determine whether a Latin word or phrase needs to be italicized. The words that appear in Black’s without italics need not be italicized in your writing.

What Are You Actually Saying

So now you know whether to use Latin and how to write it (or at least how to find out how), but do you know what the words and phrases mean? Check out the literal definitions of these commonly used legal Latin words and phrases (in quotations below) and their present usage.

A priori: “from what is before.” A priori indicates an argument derived from an earlier event.

A mensa et thoro: “from bed and table.” In family law, divorce a mensa et thoro means legal separation without a formal divorce.

Bona fide:“in good faith.” Bona fide is used to describe something genuine or earnest. For example, “a bona fide claim” is one that is not specious. Here’s a fun fact: the opposite of bona fide is mala fide. I never hear anyone say mala fide. I wonder why that didn’t catch on.

Caveat: “may he beware.” Used as a noun, a caveat is a warning or qualification.

Certiorari: “to be more fully informed; to be shown.” A writ of certiorariis a request to a court seeking judicial review.

Duces tecum: “bring with you.” A subpoena duces tecum is a summons to produce evidence for a trial.

Ex parte:“from/for one party.” When something is done ex parte, it means one party is not present. For example, ex parte communication could mean a communication between the judge and plaintiff without the defendant present.

Ex post facto: “from a thing done afterward.” This term is commonly used to mean “after the fact.”

Expresio unius est exclusio alterius: “the express mention of one thing excludes all others.” This term is often used to show exclusivity of a list (i.e., if an item is not listed, it is not included).

Ex rel.: abbreviated from ex relatione, the term ex rel. means “by relation.” Ex rel. is used to express the idea “on behalf of,” as when the government brings an action on behalf of another party.

Habeas corpus: “may you have the body.” A habeus corpus writ challenges a detention. Literally, it demands that the detaining party bring the person detained to the court reviewing the detention.

I.e.: abbreviation of id est, which means “that is.” I.e. is used to further explain something that may not have been clear. Writers tend to mix up i.e. and e.g. But e.g. stands for exampli gratia, which means “example provided.” So i.e. should precede an explanation. E.g. should precede an example.

Id.: abbreviation of idem, which means “the same.” In legal citation, id. is used to indicate that a source is identical to the preceding one.

Imprimatur: “let it be printed.” An imprimatur is permission for a document to be printed. The term is often used in the context of the Catholic Church, as in “the text carries the imprimatur of the Church.”

In forma pauperis: “in the form of a pauper.” This phrase denotes a person who cannot afford the costs of a legal proceeding. In forma pauperis status usually means the status a court has granted a party an order to waive or reduce costs of a proceeding.

Prima facie: “first sight; first view.” In the law, this word is commonly used as an adjective to suggest that an argument is factually or legally sufficient unless otherwise disproven.

Pro bono: “for the good.” Lawyers who provide pro bono service provide legal service at no charge.

Pro tem: abbreviation of pro tempore, which means “for the time being.” In legal usage, pro temis often used to describe a judge or attorney who is temporarily filling a judicial vacancy.

Quantum meruit: “as much as he deserves.” In legal terms, quantum meruit is an equitable remedy for unjust enrichment. Quantum meruit damages are awarded in an amount equal to the actual value of services rendered.

Quid pro quo: “something for something.” This term is used to suggest a favor that is done in exchange for another favor.

Respondeat superior: “let the master answer.” This term refers to vicarious liability of employers for the acts of their employees.

Sine qua non: Used to connote essence. For example, “clarity is the sine qua non of good writing.”

Sui juris: “of his own right.” A person who is sui juris may act for one’s own self to manage his affairs; he is not subject to any legal disability. For example, to enter into a valid contract, a person must be sui juris.

Ultra vires:“beyond the powers.” Ultra vires is used to describe an act that was done without the proper legal authority.

Viz.: abbreviation of videlicet, which is itself an abbreviation of videre licet, which literally means “it is permitted to see.” It’s used as a replacement for namely or that is and typically precedes a more detailed description of the concept set forth before the viz. It operates like an e.g., except that viz. suggests a nearly complete list, whereas e.g., would suggest an incomplete list of examples. (Example: “Dorothy skipped along with all her friends, viz., the Tin Man, the Cowardly Lion and Scarecrow.”)


Learning whether Latin phrases need to be italicized is easy: Look it up in a citation manual or legal dictionary. Determining when to use Latin phrases in legal writing is also fairly straightforward: avoid it if there’s a clear English equivalent. When you stumble upon a Latin phrase in legal writing or find yourself having to write one, take a moment to look it up in a legal dictionary to ensure you understand its usage or whether you should be using it at all.



1. I’m quite sure this isn’t proper Latin, but it’s as close as I could come without taking a class.

2. Nota bene: using phrases like this, whether italicized or not, might make a writer sound a little pompous.

Elizabeth Ruiz Frost teaches legal research and writing and other courses at the University of Oregon School of Law.

An archive of  The Legal Writer articles is available here.

© 2016 Elizabeth Ruiz Frost

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