Louisville Juvenile Law Lawyer, Ohio, page 6

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 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 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.

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 legal doctrine that prevents legislators from being sued for actions performed and decisions made in the course of serving in government. This doctrine does not protect legislators from criminal prosecution, nor does it relieve them from responsibility for actions outside the scope of their office, such as the nefarious activities of former Senator Bob Packwood.

A quaint phrase that refers to the recording of an arrested person's name, age, address and reason for arrest when that person is brought to jail and placed behind bars. Nowadays, the book is likely to be a computer. Usually, a mug shot and fingerprints are taken, and the arrestee's clothing and personal effects are inventoried and stored.

A mental defect or disease that makes it impossible for a person to understand the wrongfulness of his acts or, even if he understands them, to ditinguish right from wrong. Defendants who are criminally insane cannot be convicted of a crime, since criminal conduct involves the conscious intent to do wrong -- a choice that the criminally insane cannot meaningfully make. See also irresistible impulse; McNaghten Rule.

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.