Courtrooms and trials differ in size, jurisdiction, and purpose, but they all share some fundamental characteristics. For instance, civil and criminal trials are based on the adversary system. Most of us have seen these epic battles on TV shows like Law and Order. Two sides put forward their best cases. To some people that's motive for murder. Objection! That is not cross examination, that's pure speculation! Let's move on. In civil trials, the plaintiff sue the defendant for damages, and in criminal trials the prosecutor, the lawyer for the government, brings charges against the defendant. The prosecutor having already satisfied himself or herself that this is the person who committed the crime, can really roll up their sleeves and try to convince the jury that this is the person who should be punished. Then the defense counsel by the same token will roll up his or her sleeves and and fight back and say no that's not true, and really force the government to prove each element beyond a reasonable doubt. The adversary system is a very important way of determining truth. The idea is that through this exchange between the prosecutor and defense, you can begin to that out what really happened in a case. The judge is an umpire. The judge is supposed to make the legal rulings in the case, determine what evidence is admissible or not admissible. The judge will also tell the jury what the law is, so that the jury can concentrate on the facts of the case. The trial begins with an opening statement. An opening statement is the jurors' orientation to the particular case. In a criminal case, the prosecution makes an opening statement. The defense may or may not make an opening statement. In a civil case, usually both sides make it. Pay attention to opening statements, that that's going to be the key to understanding what the case is all about. It's a chance to the lawyers to tell the jurors what they think the evidence is going to show. After the opening statements, both sides get to present their evidence and their witnesses, lawyers for the plaintiff or the prosecution go first. Their questioning of the witnesses is called direct examination. The defense is then allowed to cross-examine the witnesses. Pay close attention to what people do on the witness stand and of course the demeanor of a particular witness because you're evaluating not just what the witness says, but you have to evaluate credibility. This is one of the most important roles of a jury, is just determining whether or not something and someone is believable. After the prosecution presents its case the defense gets its turn to call its own witnesses who testify and may be cross-examined by the prosecution. This is all followed by a rebuttal, often the last part of a case before the jury gets it. The very last phase of the courtroom part of the trial is the closing argument. Closing argument is a summary, it's like a conclusion. If you're the prosecutor, it better line up pretty closely with that opening statement. It is essentially a way for a prosecutor to remind the jury of all the different pieces of evidence, and how they all fit together, or on the defense side in a criminal case often here's how it didn't fit together. Here's how it fell apart. The judge will then give the jury final instructions and set the framework for deliberations. The jury takes the case to the jury room, where goes over all of the evidence testimony and arguments to reach a verdict: guilty or not guilty in a criminal case, or finding for the plaintiff or the defendant in a civil trial. If the jury finds for the plaintiff, it will usually decide the amount of damages the defendant must pay after a separate hearing. Verdicts don't have to be unanimous in a criminal trial. However if there are only six jurors, they do. It's true, while all death penalty cases must be unanimous the Supreme Court has ruled that unanimity is not a constitutional right. Criminal trials in federal courts and 48 states require unanimous verdicts in felony cases, but Oregon and Louisiana do not. And verdicts and civil trials do not have to be unanimous. If the jury cannot reach a verdict, it is called a hung jury and a mistrial is declared. The case has not been decided and the whole thing may have to start all over again with a brand new jury.