A more thorough explanation:

Law French

Law French is a type of French language that was used in England after the Norman Conquest in 1066. It became the main language of the English legal system and was used for many centuries. It was eventually replaced by Law Latin and English.

One example of Law French is the phrase "ce que dit le grant juree," which means "what the grand jury says." Another example is "attainte," which means "conviction."

These examples illustrate how Law French was used in the English legal system. It was used to describe legal concepts and procedures, and it was important for lawyers and judges to understand it in order to work in the legal system.