San Quentin Juvenile Law Lawyer, California

A formal accusation of criminal activity. The prosecuting attorney decides on the charges, after reviewing police reports, witness statements and any other evidence of wrongdoing. Formal charges are announced at an arrested person's arraignment.

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.

Circumstances that increase the seriousness or outrageousness of a given crime, and that in turn increase the wrongdoer's penalty or punishment. For example, the crime of aggravated assault is a physical attack made worse because it is committed with a dangerous weapon, results in severe bodily injury or is made in conjunction with another serious crime. Aggravated assault is usually considered a felony, punishable by a prison sentence.

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.

A deliberate act that causes harm to another, for which the victim may sue the wrongdoer for damages. Acts of domestic violence, such as assault and battery, are intentional torts (as well as crimes).

A document issued by a judge or magistrate that authorizes the police to arrest someone. Warrants are issued when law enforcement personnel present evidence to the judge or magistrate that convinces her that it is reasonably likely that a crime has taken place and that the person to be named in the warrant is criminally responsible for that crime.

A rule of evidence that disallows the use of illegally obtained evidence in criminal trials. For example, the exclusionary rule would prevent a prosecutor from introducing at trial evidence seized during an illegal search.

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.