plaintiff - The person who files the complaint in a civil lawsuit.
defendant - In a civil suit, the person complained against; in a criminal case, the person accused of the crime.
A lawyer (also called attorney, counsel, or counselor) is a licensed professional who advises and represents others in legal matter
witness - A person called upon by either side in a lawsuit to give testimony before the court or jury.
judge - Government official with authority to decide lawsuits brought before courts. Judicial officers of the Supreme Court and the highest court in each state are called justices.
jury - Persons selected according to law and sworn to inquire into and declare a verdict on matters of fact. State court juries can be as small as six jurors in some cases. Federal juries for civil suits must have six jurors criminal suits must have twelve.
Trial
After many weeks or months of preparation, the prosecutor is ready for the most important part of his job: the trial. The trial is a structured process where the facts of a case are presented to a jury, and they decide if the defendant is guilty or not guilty of the charge offered. During trial, the prosecutor uses witnesses and evidence to prove to the jury that the defendant committed the crime(s). The defendant, represented by an attorney, also tells his side of the story using witnesses and evidence.
In a trial, the judge — the impartial person in charge of the trial — decides what evidence can be shown to the jury. A judge is similar to a referee in a game, they are not there to play for one side or the other but to make sure the entire process is played fairly.
Jury Instructions
Following the closing arguments, the judge “charges the jury,” or informs them of the appropriate law and of what they must do to reach a verdict.
Jury Deliberations & Announcement of the Verdict
After being charged, the jury goes into deliberation, the process of deciding whether a defendant is guilty or not guilty. During this process, no one associated with the trial can contact the jury without the judges and lawyers. If the jury has a question on the law, they must write a note to the judge, which the judge will read in court with all parties present. In federal criminal trials, the jury must reach a unanimous decision in order to convict the defendant.
After they reach an agreement on a verdict, they notify the judge, the lawyers, and the defendant in open court. Everyone is present in court for the reading of the verdict. The United States Marshals Service is present during trial to protect the judge and prosecutors from potential harm. If the defendant is found not guilty, they are usually free to go home.