In some times and places accessories have been subject to lesser penalties than principals (the persons who actually commit the crime).
Common law traditionally considers an accessory just as guilty as the principal(s) in a crime, and subject to the same penalties.
Furthermore, there must be proof that the accessory knew that his or her action, or inaction, was helping the criminals commit the crime, or evade detection, or escape.
This is related to the traditional privilege not to testify against an accused spouse, and the older idea that a wife was completely subject to the orders of a husband, whether lawful or illegal.
The term "accessory" derives from the English common law and has been inherited by those countries with a more or less Anglo-American legal system.
The specific terms accessory-before-the-fact and accessory-after-the-fact were used in England and the United States but are now more common in historical than in current usage.
AN accessory is he who is not the chief actor in the offense, nor present at its performance, but is someway concerned therein, either before or after the fact committed.He goes on to define an accessory-before-the-fact in these words: As to the second point, who may be an accessory before the fact; Sir Matthew Hale 12 defines him to be one, who being absent at the time of the crime committed, does yet procure, counsel, or command another to commit a crime.
As furnishing him with a horse to escape his pursuers, money or victuals to support him, a house or other shelter to conceal him, or open force and violence to rescue or protect him.The Criminal Code has several sections which deal with accessory to offences: For these purposes, abetting means "to encourage or set on" and an abettor is "an instigator or setter on, one who promotes or procures a crime to be committed".
Note that under s. 21(2), the words "ought to have known" indicating objective knowledge have been ruled unconstitutional by the Supreme Court of Canada in cases where the principal offence requires subjective foresight of the consequences, such as murder (R v Logan, [1990] 2 SCR 731).
In R v Coney (1882) 8 QBD 534, where a crowd watched an illegal prize fight, it was held that there must be active, not mere passive, encouragement.
R. 326 it was held a reasonable inference that a company, knowing that its employees are acting illegally and deliberately doing nothing to prevent it from being repeated, actually intends to encourage the repetition.
Gillick v West Norfolk and Wisbech Area Health Authority (1986) AC 112 is an example of a type of case where the uncertainties of the precise meaning of intention effectively confer a sometimes-welcome discretion on whether to impose responsibility.
One rationale for the decision would be that a jury would not infer intention in such circumstances if they thought that the doctor was acting in what he considered to be the girl's best interests.
Federal law defines accessories after the fact as persons who provide criminals with certain aid in order to hinder a criminal's apprehension or prosecution:[8] Whoever, knowing that an offense against the United States has been committed, receives, relieves, comforts or assists the offender in order to hinder or prevent his apprehension, trial or punishment, is an accessory after the fact.