Yale Juvenile Law Lawyer, Oklahoma

The earliest and most common test for criminal insanity, in which a criminal defendant is judged legally insane only if he could not distinguish right from wrong at the time he committed the crime. For example, a delusional psychotic who believed that his assaultive acts were in response to the will of God would not be criminally responsible for his acts.

An affirmative defense to a crime. Self-defense is the use of reasonable force to protect oneself from an aggressor. Self-defense shields a person from criminal liability for the harm inflicted on the aggressor. For example, a robbery victim who takes the robber's weapon and uses it against the robber during a struggle won't be liable for assault and battery since he can show that his action was reasonably necessary to protect himself from imminent harm.

A peace officer for a particular geographic area -- most often a rural county -- who commonly has the power to serve legal papers, arrest lawbreakers and keep the peace. Depending on the state, a constable may be similar to a marshal or sheriff.

The well-known term for an Alien Registration Receipt Card. This plastic photo identification card is given to individuals who are legal permanent residents of the United States. It serves as a U.S. entry document in place of a visa, enabling permanent residents to return to the United States after temporary absences. The key characteristic of a green card is that it allows the holder to live permanently in the United States. Unless you abandon your residence or violate certain criminal or immigration laws, your green card can never be taken away. Possession of a green card also allows you to work in the United States legally. Those who hold green cards for a certain length of time may eventually apply for U.S. citizenship. Green cards have an expiration date of ten years from issuance. This does not mean that your permanent resident status expires. You must simply apply for a new card.

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.

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.

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.

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.