Standard Juvenile Law Lawyer, Illinois

A situation in which the police detain a person in a manner that, to any reasonable person, makes it clear she is not free to leave. A person can be 'under arrest' even though the police have not announced it; nor are handcuffs or physical restraint necessary. Questioning an arrested person about her involvement in or knowledge of a crime must be preceded by the Miranda warnings if the police intend to use the answers against the person in a criminal case. If the arrested person chooses to remain silent, the questioning must stop.

The mental component of criminal liability. To be guilty of most crimes, a defendant must have committed the criminal act (the actus reus) in a certain mental state (the mens rea). The mens rea of robbery, for example, is the intent to permanently deprive the owner of his property.

An order signed by a judge that directs owners of private property to allow the police to enter and search for items named in the warrant. The judge won't issue the warrant unless she has been convinced that there is probable cause for the search -- that reliable evidence shows that it's more likely than not that a crime has occurred and that the items sought by the police are connected with it and will be found at the location named in the warrant. In limited situations the police may search without a warrant, but they cannot use what they find at trial if the defense can show that there was no probable cause for the search.

A decision by the jury to acquit a defendant who has violated a law that the jury believes is unjust or wrong. Jury nullification has always been an option for juries in England and the United States, although judges will prevent a defense lawyer from urging the jury to acquit on this basis. Nullification was evident during the Vietnam war (when selective service protesters were acquitted by juries opposed to the war) and currently appears in criminal cases when the jury disagrees with the punishment--for example, in 'three strikes' cases when the jury realizes that conviction of a relatively minor offense will result in lifetime imprisonment.

Laws written by Congress and state legislators that make certain behavior illegal and punishable by fines and/or imprisonment. By contrast, civil laws are not punishable by imprisonment. In order to be found guilty of a criminal law, the prosecution must show that the defendant intended to act as he did; in civil law, you may sometimes be responsible for your actions even though you did not intend the consequences. For example, civil law makes you financially responsible for a car accident you caused but didn't intend.

Criminal Law Traffic TicketshomeGLOSSARY jury A group of people selected to apply the law, as stated by the judge, to the facts of a case and render a decision, called the verdict. Traditionally, an American jury was made up of 12 people who had to arrive at a unanimous decision. But today, in many states, juries in civil cases may be composed of as few as six members and non-unanimous verdicts may be permitted. (Most states still require 12-person, unanimous verdicts for criminal trials.) Tracing its history back over 1,000 years, the jury system was brought to England by William the Conqueror in 1066. The philosophy behind the jury system is that--especially in a criminal case--an accused's guilt or innocence should be judged by a group of people from her community ('a jury of her peers'). Recently, some courts have been experimenting with increasing the traditionally rather passive role of the jury by encouraging jurors to take notes and ask questions.

A ruling by a judge, typically made after the plaintiff has presented all of her evidence but before the defendant puts on his case, that awards judgment to the defendant. A directed verdict is usually made because the judge concludes the plaintiff has failed to offer the minimum amount of evidence to prove her case even if there were no opposition. In other words, the judge is saying that, as a matter of law, no reasonable jury could decide in the plaintiff's favor. In a criminal case, a directed verdict is a judgement of acquittal for the defendant.

A formal investigation -- governed by court rules -- that is conducted before trial. Discovery allows one party to question other parties, and sometimes witnesses. It also allows one party to force the others to produce requested documents or other physical evidence. The most common types of discovery are interrogatories, consisting of written questions the other party must answer under penalty of perjury, and depositions, which involve an in-person session at which one party to a lawsuit has the opportunity to ask oral questions of the other party or her witnesses under oath while a written transcript is made by a court reporter. Other types of pretrial discovery consist of written requests to produce documents and requests for admissions, by which one party asks the other to admit or deny key facts in the case. One major purpose of discovery is to assess the strength or weakness of an opponent's case, with the idea of opening settlement talks. Another is to gather information to use at trial. Discovery is also present in criminal cases, in which by law the prosecutor must turn over to the defense any witness statements and any evidence that might tend to exonerate the defendant. Depending on the rules of the court, the defendant may also be obliged to share evidence with the prosecutor.