Lavinia Juvenile Law Lawyer, Tennessee

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.

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.

The earliest and most common test for criminal insanity, in which a criminal defendant is judged legally insane only if he could not distinguish right from wrong at the time he committed the crime. For example, a delusional psychotic who believed that his assaultive acts were in response to the will of God would not be criminally responsible for his acts.

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.

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.

Another term for theft. Although the definition of this term differs from state to state, it typically means taking property belonging to another with the intent to permanently deprive the owner of the property. If the taking is non forceful, it is larceny; if it is accompanied by force or fear directed against a person, it is robbery, a much more serious offense.

Laws written by Congress and state legislators that make certain behavior illegal and punishable by fines and/or imprisonment. By contrast, civil laws are not punishable by imprisonment. In order to be found guilty of a criminal law, the prosecution must show that the defendant intended to act as he did; in civil law, you may sometimes be responsible for your actions even though you did not intend the consequences. For example, civil law makes you financially responsible for a car accident you caused but didn't intend.

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.

The amount and quality of information police must have before they can arrest or search without a warrant or that a judge must have before she will sign a search warrant allowing the police to conduct a search or arrest a suspect. Reliable information must show that it's more likely than not that a crime has occurred and the suspect is involved.