Thornton Juvenile Law Lawyer, Pennsylvania

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.

Evidence that proves a fact by means of an inference. For example, from the evidence that a person was seen running away from the scene of a crime, a judge or jury may infer that the person committed the crime.

A mental defect or disease that makes it impossible for a person to understand the wrongfulness of his acts or, even if he understands them, to ditinguish right from wrong. Defendants who are criminally insane cannot be convicted of a crime, since criminal conduct involves the conscious intent to do wrong -- a choice that the criminally insane cannot meaningfully make. See also irresistible impulse; McNaghten Rule.

Someone who helps another person (known as the principal) commit a crime. Unlike an accessory, an accomplice is usually present when the crime is committed. An accomplice is guilty of the same offense and usually receives the same sentence as the principal. For instance, the driver of the getaway car for a burglary is an accomplice and will be guilty of the burglary even though he may not have entered the building.

A document issued by a judge or magistrate that authorizes the police to arrest someone. Warrants are issued when law enforcement personnel present evidence to the judge or magistrate that convinces her that it is reasonably likely that a crime has taken place and that the person to be named in the warrant is criminally responsible for that crime.

A term lawyers use to describe the courts and other bureaucracies that handle American's criminal legal business, including offices of various state and federal prosecutors and public defenders. Many people caught up in this system refer to it by less flattering names.

A negotiation between the defense and prosecution (and sometimes the judge) that settles a criminal case. The defendant typically pleads guilty to a lesser crime (or fewer charges) than originally charged, in exchange for a guaranteed sentence that is shorter than what the defendant could face if convicted at trial. The prosecution gets the certainty of a conviction and a known sentence; the defendant avoids the risk of a higher sentence; and the judge gets to move on to other cases.

A plea entered by the defendant in response to being charged with a crime. If a defendant pleads nolo contendere, she neither admits nor denies that she committed the crime, but agrees to a punishment (usually a fine or jail time) as if guilty. Usually, this type of plea is entered because it can't be used as an admission of guilt if a civil case is held after the criminal trial.

Punishment in a criminal case. A sentence can range from a fine and community service to life imprisonment or death. For most crimes, the sentence is chosen by the trial judge; the jury chooses the sentence only in a capital case, when it must choose between life in prison without parole and death.