When you start studying law, you quickly grasp the fact you’ll often come across Latin phrases. I will say as you learn them and come across them more often, you can start to figure out what they mean on your own. At least, during my time in undergrad that was my case.
Even though I have only gone through pre-law, I have absolutely come across all of these words/phrases and it was only after I knew what the word meant that I could fully understand what I was reading. Below are what I have found to be some of the more common words you’ll run into as you start learning and working with legal documents. All definitions are from Black’s Law Dictionary, 9th Edition. The sites used to help make this list also linked below!
1. Mens Rea:
“[Law Latin ‘guilty mind’] (1861)The state of mind that the prosecution, to secure a conviction, must prove that a defendant had when committing a crime; criminal intent or recklessness <the mens rea for theft is the intent to deprive the rightful owner of the property>.| Mens rea is the second of two essential elements of every crime at common law, the other being the actus reus. – Also termed mental element; criminal intent; guilty mind.“
(page 1075)
This is one of the two things that you need to convict someone (the second is next). A mens rea means that you know what you were doing and you had a ‘guilty mind.’ If you look at the example included in the definition, it shows that the thief knew they were going and taking something that did not belong to them.
This is why people can sometimes get off with an insanity plea. It doesn’t always get a defendant off but if you can prove they were “insane” and weren’t in their right mind, then they didn’t have a mens rea. Their mind wasn’t totally in the crime. This is also why people don’t always automatically go to jail when they murder someone. If you can prove a murder was purely accidental, you probably won’t be convicted of a charge.
2. Actus Reus:
“[Law Latin ‘guilty act’] (1902) The wrongful deed that comprises the physical components of a crime and that generally must be couples with mens rea to establish criminal liability; a forbidden act <the actus reus for theft is the taking of or unlawful control over property without the owner’s consent>. – Also termed deed of crime; overt act.” (page 41)
This is the second necessity when making a conviction. This is the actual guilty act. The example in this definition shows that the actus reus is when the thief goes and takes whatever it may be. In the United States, you cannot convict someone of thinking – no matter what that may be. You can think up an entire murder plot, but unless you act on it, you won’t be convicted.
3. De Novo:
“adj. (1536) Anew.” (page 500)
In Latin, the word means new, and in Black’s Law Dictionary there were many phrases listed under this definition that include “de novo.” There’s hearing de novo, trial de novo, de novo judicial review, de novo review, etc. I am sure you can put it together. Hearing de novo would be a new hearing. Trial de novo is a new trial, and so on. This would likely be seen mostly in appellate (appeals) proceedings.
4. Amicus Curiae:
“[Latin ‘friend of the court’ (17c) A person who is not a party to a lawsuit but who petitions the court or is requested by the court to file a brief in action because that person has a strong interest in the subject matter. – Often shortened to amicus – Also termed friend of the court.” (page 98)
This is another word you hear usually in appellate situations. In undergrad, I usually heard this when talking about SCOTUS and federal cases. It is rare in the lower courts and courts with original jurisdiction because those are usually going to focus on trials and finding facts. You may find these in the more complex and high-profile cases – but it is super, super rare.
The purpose of an amicus is for someone (usually in a higher position somewhere) to offer exterior information from the case. Like the definition is not a party to the case, so they’re just offering a perspective that may help a court decide on which way to go. On cases that are high up, you can see many amicus briefs that are sent by those who are very knowledgeable and/or experienced on the subject that is being debated on. They help straighten out the complexity that is usually within cases that benefit off these briefs.
5. Certiorari/Writ of Certiorari/Cert/Writ of Cert:
“[Law Latin ‘to be more fully informed’] (15c) An extraordinary writ issued by an appellate court, at its discretion, directing a lower court to send the record for review. | The writ evolved from one of the prerogative writs of the English Court of King’s Bench, and in the United States it became a general appellate remedy. The U.S. Supreme Court uses certiorari to review most of the cases it decides to hear. – Abbr. cert. – Also termed writ of certiorari.” (page 258)
As the definition says, this is for appellate courts. This is essentially when a higher court is asked to review the decision of a lower court. If “cert” is granted, then the higher court has agreed to review the lower courts decision. This is how SCOTUS gets most of their cases. As you probably have learned if you’re a student, SCOTUS only grants cert to few cases.
6. Mandamus/Writ of Mandamus:
“[Latin ‘we command’] (16c) A writ issued by a court to compel performance of a particular act by a lower court or a governmental officer or body, usu. to correct a prior action or failure to act. – Also termed writ of mandamus; mandate; (in BrE) order.” (page 1046-1047)
This is one you won’t hear as often since it is considered a more extreme remedy. This is used to force someone to carry out their legal duties. This is often used when the only solution/remedy to the issue is for someone to do what they were legally supposed to do. For example, if a court is dragging a case for years, and the dragging of the case is negatively effecting the rights of a party to the case, a higher/appellate court can issue this writ and force them to decide. This can also make an agency enforce laws if they aren’t doing so and things of that nature.
It is important to note that this is used to make someone to something they are required by law to do, this cannot be used to make someone do something they can legally choose not to do.
7. Habeas Corpus/Writ of Habeas Corpus:
“[Latin Law “that you have the body”] (18c) A writ employed to bring a person before a court, most frequently to ensure that the person’s imprisonment or detention is not illegal (habeas corpus as subjiciendum). | In addition to being used to test the legality of an arrest or commitment, the writ may be used to obtain judicial review of (1) the regularity of the extradition process, (2) the right to or amount of bail, or (3) the jurisdiction of a court that has imposed a criminal sentence. – Abbr. H.C. – Sometimes shortened to habeas. – Also termed writ of habeas corpus; Great Writ.” (page 778)
This essentially ensures that someone is arrested for a valid reason. This is usually used when someone has been arrested/detained but there isn’t a valid and formal reason behind it. The detainee or someone acting on behalf of the detainee can file this, and it would force the court to face him/her and either release him or formally charge them with something that makes their arrest valid.
8. Per Curiam:
“adv. & adj. [Latin] (15c) By the court as a whole.” (page 1251)
When you see this, you’ll probably be reading about a case. You’d see this on a document because it means the whole court made this decision. If you see this on a SCOTUS case then it could signal a unanimous decision (but it does not always mean unanimous). Per curiam is used in place of writing all the names of those who helped make the decision and means the court is issuing their opinion as a singular voice.
9. Pro Se:
“adv. & adj. [Latin](1817) For one self; on one’s own behalf; without a lawyer <the defendant proceeded pro se> <a pro se defendant>. – Also termed pro persona; in propria persona; pro per.“(page 1341)
If you are reading a legal document and you see this, it means someone was representing themselves. It is used as a label to indicate their lack of representation. You may see this in self-help legal resources. If you are representing yourself and signing something, you could label your name with ‘pro se’ at the end of it as well. Usually, if you are representing yourself, there are specific instructions and simplified resources for you labelled with pro se. If you’re a student and you’re reading this, you may also see this within hypotheticals you are presented with.
10. De Facto:
“[Law Latin ‘in point of fact’] (17c) 1. Actual; existing in fact; having effect even though not formally or legally recognized <a de facto contract> 2. Illegitimate but in effect <a de facto government>.” (page 479)
As the definition says, it’s something in effect that was/ has never been recognized. In Black’s Law Dictionary there were a few entries that you may see: De facto adoption, de facto marriage, de facto contract of sale, etc. A de facto marriage would be when two people call each other as their spouse, live together, etc., but they never signed a marriage license that formally/legally recognized. A de facto situation does not mean they’re saying what has been done isn’t real, it just might not hold up in a court of law.
There’s so much more Legal Latin you can come by, and there can be instances where you can’t just figure out it’s meaning by just looking at the word. I highly suggest getting your hands on the more recent versions of Black’s Law Dictionary. You don’t have to blow the money to buy one either! You can likely find a copy at your local public library – that’s where I found mine to find these definitions. Along with that, the definitions and examples here are fairly simplified, so make sure you do your research to get the most detailed information.
With so many more legal words to understand, be sure to also keep watch for Legal Latin part 2 and other vocab oriented posts!!
With that being said, nothing I say or explain here should be taken as legal advice! I am not (yet) qualified to provide any type of legal advice to anyone. All information here is based on my own research and what I’ve learned during my time at the University of Kentucky. If I pull information from other sources, I always make sure to give credit where its due.
Thanks for reading!
Lacey
All definitions from Black’s Law Dictionary, 9th Edition
https://jdadvising.com/top-10-latin-words-for-law-student
https://testmaxprep.com/blog/lsat/15-latin-legal-terms-every-1l-should-know
https://www.ohiolegalhelp.org/legally-informed-latin-legal-terms-060223