Casey Juvenile Law Lawyer, Iowa

To intentionally destroy, obliterate or strike out records or information in files, computers and other depositories. For example, state law may allow the criminal records of a juvenile offender to be expunged when he reaches the age of majority, to allow him to begin his adult life with a clean record. Or, a company or government agency may routinely expunge out-of-date records to save storage space.

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.

(1) To discredit. To impeach a witness' credibility, for example, is to show that the witness is not believable. A witness may be impeached by showing that he has made statements that are inconsistent with his present testimony, or that he has a reputation for not being a truthful person. (2) The process of charging a public official, such as the President or a federal judge, with a crime or misconduct and removing the official from office.

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.

One of the most sacred principles in the American criminal justice system, holding that a defendant is innocent until proven guilty. In other words, the prosecution must prove, beyond a reasonable doubt, each element of the crime charged.

A legal doctrine that prevents legislators from being sued for actions performed and decisions made in the course of serving in government. This doctrine does not protect legislators from criminal prosecution, nor does it relieve them from responsibility for actions outside the scope of their office, such as the nefarious activities of former Senator Bob Packwood.

The component parts of crimes. For example, 'Robbery' is defined as the taking and carrying away of property of another by force or fear with the intent to permanently deprive the owner of the property. Each of those four parts is an element that the prosecution must prove beyond a reasonable doubt.

A quaint phrase that refers to the recording of an arrested person's name, age, address and reason for arrest when that person is brought to jail and placed behind bars. Nowadays, the book is likely to be a computer. Usually, a mug shot and fingerprints are taken, and the arrestee's clothing and personal effects are inventoried and stored.