Law French is an archaic language based on Norman and Anglo-Norman. It was used in the law courts of Great Britain, beginning with the Norman Conquest by William the Conqueror. Its use continued for several centuries in the courts of England.

In its later years, Law French became increasingly artificial, and its vocabulary became increasingly English, as it was used solely by English lawyers and judges who often spoke no real French. A frequently quoted example of this mixed English-French language comes from a marginal note printed in Dyer's Reports in the 17th century, discussing the case of a prisoner who "ject un Brickbat a le dit Justice que narrowly mist" ("threw a brickbat at the said Justice, which narrowly missed").

The inverted syntax of many legal noun phrases in English — attorney general, fee simple — is a heritage from Law French. Many of the terms of Law French have been converted into modern English in the 20th century to make the law more understandable in common law jurisdictions. However, some key terms remain from Law French, including the following:

• attorney, one appointed to act for another - now characterized as either:
  • attorney-at-law - see lawyer, solicitor, barrister or civil law notary
  • attorney-in-fact - see power of attorney.
• autrefois acquit, previously acquitted of a crime.
• bailiff, the marshal of the court, charged now chiefly with keeping order in the courtroom.
• cestui que trust , sometimes shortened to cestui; the beneficiary of a trust.
• cy-pres doctrine , the power of a court to transfer the property of one charitable trust to another charitable trust when the first trust may no longer exist or be able to operate.
• defendant, the party against whom a civil proceeding is brought.
• escheat, reversion of unclaimed property to a feudal lord, or the state where the property is allodial.
• estoppel, prevention of a party from contradicting a position previously taken.
• laches, loss of rights through failure to act.
• mortgage, literally a "dead pledge"; a pledge by which the landowner remained in possession of the property he staked as security.
• mortmain, a statute restricting the conveyance of land to the "dead hand" of a religious organization
• oyez , often calqued as hear ye!, a traditional cry used to open court proceedings, still used in the Supreme Court of the United States.
• peine forte et dure, the former practice of pressing a recalcitrant accused with weights until he entered a plea of guilty or not guilty and submitted to the jurisdiction of the court.
• plaintiff, the person who begins a lawsuit.
• prochein ami , now usually calqued as next friend; someone who files a lawsuit on behalf of another who is not capable of acting on his or her own behalf.
• profit a prendre, also known as the right of common, where one has the right to take the "fruits" of the property of another, such as mining rights, growing rights, etc.
• replevin, a suit to recover personal property unlawfully taken.
• torts, meaning wrongs.
• trove, as in treasure trove, is an adjective, not a noun, and means found. Thus treasure trove means not a treasure chest or hoard, but a treasure found by chance, as opposed to one stolen, inherited, bought, etc.
• voir dire, literally to see (someone) say; the questions a prospective juror or witness must answer to determine her or his qualification to serve, in the law of England a mini-trial held after a plea of guilty has been entered to determine the facts of the offence where they are in dispute.

See also

• French phrases used by English speakers