Songjiang Juvenile Law Lawyer, China

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.

A crime, less serious than a felony, punishable by no more than one year in jail. Petty theft (of articles worth less than a certain amount), first-time drunk driving and leaving the scene of an accident are all common misdemeanors.

In criminal cases, a group that decides whether there is enough evidence to justify an indictment (formal charges) and a trial. A grand jury indictment is the first step, after arrest, in any formal prosecution of a felony.

An exception to the general rule that a police officer needs an arrest warrant before he can enter a home to make an arrest. If a felony has just occurred and an officer has chased a suspect to a private house, the officer can forcefully enter the house in order to prevent the suspect from escaping or hiding or destroying evidence.

A ruling by a judge, typically made after the plaintiff has presented all of her evidence but before the defendant puts on his case, that awards judgment to the defendant. A directed verdict is usually made because the judge concludes the plaintiff has failed to offer the minimum amount of evidence to prove her case even if there were no opposition. In other words, the judge is saying that, as a matter of law, no reasonable jury could decide in the plaintiff's favor. In a criminal case, a directed verdict is a judgement of acquittal for the defendant.

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 jury unable to come to a final decision, resulting in a mistrial. Judges do their best to avoid hung juries, typically sending juries back into deliberations with an assurance (sometimes known as a 'dynamite charge') that they will be able to reach a decision if they try harder. If a mistrial is declared, the case is tried again unless the parties settle the case (in a civil case) or the prosecution dismisses the charges or offers a plea bargain (in a criminal case).

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.