La Farge Criminal Lawyer, Wisconsin

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.

Latin for a 'guilty act.' The actus reus is the act which, in combination with a certain mental state, such as intent or recklessness, constitutes a crime. For example, the crime of theft requires physically taking something (the actus reus) coupled with the intent to permanently deprive the owner of the object (the mental state, or mens rea).

A trial that ends prematurely and without a judgment, due either to a mistake that jeopardizes a party's right to a fair trial or to a jury that can't agree on a verdict (a hung jury) If a judge declares a mistrial in a civil case, he or she will direct that the case be set for a new trial at a future date. Mistrials in criminal cases can result in a retrial, a plea bargain or a dismissal of the charges.

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.

(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.

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.

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.

Latin for 'You have the body.' A prisoner files a petition for writ of habeas corpus in order to challenge the authority of the prison or jail warden to continue to hold him. If the judge orders a hearing after reading the writ, the prisoner gets to argue that his confinement is illegal. These writs are frequently filed by convicted prisoners who challenge their conviction on the grounds that the trial attorney failed to prepare the defense and was incompetent. Prisoners sentenced to death also file habeas petitions challenging the constitutionality of the state death penalty law. Habeas writs are different from and do not replace appeals, which are arguments for reversal of a conviction based on claims that the judge conducted the trial improperly. Often, convicted prisoners file both.

The crime of operating a motor vehicle while under the influence of alcohol or drugs, including prescription drugs. Complete intoxication is not required; the level of alcohol or drugs in the driver's body must simply be enough to prevent him from thinking clearly or driving safely. State laws specify the levels of blood alcohol content at which a person is presumed to be under the influence. Also called driving while intoxicated (DWI and drunk driving).