Most attorneys like using Latin terms. The reason for this is because the legal system of ancient Rome had a significant impact on the legal systems of most Western countries. After all, the Romans once dominated the majority of Europe, the Middle East, and North Africa. As such, it's not surprising that many legal terms have Roman origins.
For example, "actio pâcivie" means "civil action." This term can be found in American law books as well as British ones. Similarly, "adverse possession" refers to the right of one person to occupy land that another person owns. This practice was called "unlawful occupation" in medieval England but now is more commonly known as "hostile occupation."
The first thing you need to know about lawyers is that they like words that have been around for a long time. They believe that these words have been carefully selected by other lawyers who have used them before them. Using these words makes them seem important and respected by their peers.
Second, lawyers use Latin because it sounds serious. When you see a word that starts with "ex" or "ob" it means that something legal is about to start. For example, ex parte means "without notice," which indicates that the party not giving notice does not have to provide any evidence when the other party requests it.
What is the most plausible cause for the abundance of Latin words in American law? Because the church ordered it should be kept secret in order to ensure that it is understood globally because many of its key ideas are based on Roman law.
American lawyers have always been interested in adapting foreign legal systems to local conditions. The first systematic effort to do this was made by William Blackstone, who in his two-volume Commentaries on the Laws of England (1765 and 1769) described the common law as "the great bulwark of human rights" and the civil law as "the perfection of justice." He also explained that the best source for learning about both systems was Europe itself. Indeed, before the development of American jurisprudence, Europeans often looked to America for guidance on how to structure their own legal systems.
As part of this effort, American lawyers introduced many terms from the Latin language into English law. For example, "act of parliament" came from the French par l'ordre du roi (by the order of the king). "Bill of rights" comes from the Germanic word bille meaning 'a bill'. "Common law" comes from the Anglo-Saxon word comon meaning 'for the community' while "civil law" comes from the Latin word civile meaning 'of or relating to a city-state'.
The United States' present legal system has its origins in ancient Rome. Simply because the ancient Romans once conquered the majority of what is now Europe. Because our legal system is based on the Common Law of Rome, the Latin phrases employed in the Common Law of Rome have been adapted to our legal system.
In the United States, most states have their own constitutions that set out how they are to be run and their own laws that define what crimes there are in those states. Some states also have their own courts that try cases involving their residents. Other states use judicial systems based on the federal court system. These other states are called "common law" states. The language used in their constitutions and statutes is similar to that of the U.S. Constitution and Code at times because members of these state legislatures or their lawyers were not able to get access to the American documents during their development of their own legal systems.
When states join together into a union, they often create agencies that work across state lines. Examples include the FBI, the DEA, and the CDC. These organizations depend on a network of employees who can communicate easily with one another. So, to make sure this communication happens, some kind of language is needed. In many cases, members of these agency boards are appointed by the governors of the states where they work. So, again, someone has to translate what the board members think they're being asked into something writeable down.