Lansing Juvenile Law Lawyer, West Virginia

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 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 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.

A method of paying a lawyer for legal representation by which, instead of an hourly or per job fee, the lawyer receives a percentage of the money her client obtains after settling or winning the case. Often contingency fee agreements -- which are most commonly used in personal injury cases -- award the successful lawyer between 20% and 50% of the amount recovered. Lawyers representing defendants charged with crimes may not charge contingency fees. In most states, contingency fee agreements must be in writing.

(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.

A plea entered by the defendant in response to being charged with a crime. If a defendant pleads nolo contendere, she neither admits nor denies that she committed the crime, but agrees to a punishment (usually a fine or jail time) as if guilty. Usually, this type of plea is entered because it can't be used as an admission of guilt if a civil case is held after the criminal trial.

A term that describes vigorous questioning, usually by the police of a suspect in custody. Other than providing his name and address, the suspect is not obligated to answer the questions, and the fact that he has remained silent generally cannot be used by the prosecution to help prove that he is guilty of a crime. If the suspect has asked for a lawyer, the police must cease questioning. If they do not, they cannot use the answers against the suspect at trial.

Someone who helps another person (known as the principal) commit a crime. Unlike an accessory, an accomplice is usually present when the crime is committed. An accomplice is guilty of the same offense and usually receives the same sentence as the principal. For instance, the driver of the getaway car for a burglary is an accomplice and will be guilty of the burglary even though he may not have entered the building.