In law knowledge
is one of the degrees of mens rea
that constitute part of a crime
. For example, in English law
, the offence of knowingly
being a passenger in a vehicle taken without consent (TWOC
) requires that the procecution prove
, not only that the defendant was a passenger in a vehicle and that it was taken by the driver without consent, the prosecution must also prove that the defendant knew
that it was taken without consent.
Under the principle of ignorantia juris non excusat, ignorance of or mistake about the law is no defence. The mens rea of knowledge refers to knowledge about certain facts. It is "a positive belief that a state of affairs exists.
Knowledge can be:
A defendant does not have actual knowledge
if he believes something to the contrary. The standard is subjective and the belief of the defendant need not be reasonable
, only honest
. For example, in R v. Williams
the defendant intervened in what he thought was a mugging
but was in fact a citizen's arrest
. His mistake was upheld as a defence against a charge of assault
. In Beckford v. R
the defendant was a police officer
who shot and killed V. Beckford claimed that he believed that V was shooting at him. It was found that the correct test was whether D "honestly believed" facts which, if true, would establish a defence. The reasonableness of the belief would be evidential
in finding whether it was truly believed.
is also found where a defendant suspects that circumstances exist and "deliberately decides not to make any further enquiries" in case his suspicions prove well founded. A common example is a person who purchases signally inexpensive and unprovenanced
, but desirable items from a stranger. Such a person is likely to be fixed with constructive knowledge
that the items were stolen
This is relevant in strict liability
offences and in corporate crime
. For example, if a bar manager delegates his duties to others and those others know of unlawful activities on the premises, the manager can be fixed with imputed knowledge
of the unlawful activities.