Langston Juvenile Law Lawyer, Oklahoma

A signed statement, sworn to be true by the signer, that will make the signer guilty of the crime of perjury if the statement is shown to be materially false -- that is, the lie is relevant and significant to the case.

(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.

Revealing one's genitals under circumstances likely to offend others. Exposure is indecent under the law whenever a reasonable person would or should know that his act may be seen by others--for example, in a public place or through an open window--and that it is likely to cause affront or alarm. Indecent exposure is considered a misdemeanor in most states.

A decision by a judge or jury that a defendant in a criminal case is not guilty of a crime. An acquittal is not a finding of innocence; it is simply a conclusion that the prosecution has not proved its case beyond a reasonable doubt.

A minor violation of the law that is punishable only by a fine--for example, a traffic or parking ticket. Not all vehicle-related violations are infractions, however--refusing to identify oneself when involved in an accident is a misdemeanor in some states.

Testimony or other evidence that fails to meet state or federal court rules governing the types of evidence that can be presented to a judge or jury. The main reason why evidence is ruled inadmissible is because it falls into a category deemed so unreliable that a court should not consider it as part of a deciding a case --for example, hearsay evidence, or an expert's opinion that is not based on facts generally accepted in the field. Evidence will also be declared inadmissible if it suffers from some other defect--for example, as compared to its value, it will take too long to present or risks enflaming the jury, as might be the case with graphic pictures of a homicide victim. In addition, in criminal cases, evidence that is gathered using illegal methods is commonly ruled inadmissible. Because the rules of evidence are so complicated (and because contesting lawyers waste so much time arguing over them) there is a strong trend towards using mediation or arbitration to resolve civil disputes. In mediation and arbitration, virtually all evidence can be considered. See evidence, admissible evidence.

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.

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.