Hen Island Juvenile Law Lawyer, Ontario, page 2

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.

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.

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.

An order signed by a judge that directs owners of private property to allow the police to enter and search for items named in the warrant. The judge won't issue the warrant unless she has been convinced that there is probable cause for the search -- that reliable evidence shows that it's more likely than not that a crime has occurred and that the items sought by the police are connected with it and will be found at the location named in the warrant. In limited situations the police may search without a warrant, but they cannot use what they find at trial if the defense can show that there was no probable cause for the search.

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.

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).

Listening to conversations or observing conduct which is meant to be private, typically by using devices that amplify sound or light, such as stethoscopes or binoculars. The term comes from the common law offense of listening to private conversations by crouching under the windows or eaves of a house. Nowadays, eavesdropping includes using electronic equipment to intercept telephone or other wire communications, or radio equipment to intercept broadcast communications. Generally, the term 'eavesdropping' is used when the activity is not legally authorized by a search warrant or court order; and the term 'surveillance' is used when the activity is permitted by law. Compare electronic surveillance.